bluuebunny/crossref_metadata_2025_split huggingface dataset:
Secondary ion yield enhancement in organic samples due to Au/Pt nanoparticle condensation and their substrate effects
Authors: Prabhakaran A. , Yunus S. , Wehbe N. , Bertrand P. , Delcorte A. 
Published: June 2010

AbstractUpon atomic ion bombardment, metal nanoparticles at the surface of organic materials (polymers, additives, biomolecules) induce a strong increase of the analytically significant sample ion yields in secondary ion mass spectrometry. In order to unravel the physics behind the Metal Assisted SIMS (MetA SIMS) effect, this study focuses, first, on the comparison between thin layers of polystyrene (PS) on gold‐covered substrates and thick layers of PS covered with different thicknesses of Au. The evolutions of the characteristic fragment ion yields are almost identical up to 8 nm equivalent Au thickness but the yields of Au‐cationized oligomers are consistently one order of magnitude larger when gold is used as substrate. This difference might be due to the limited diffusion of PS on the Au condensates. Second, the effect of Au and Pt on the ion yield enhancement has been studied by casting thin layers of PS on Au and Pt‐covered Si substrates. The Au and Pt‐induced fragment ion yields evolve similarly with the metal thickness up to 6 nm. The yields of metal cationized oligomers, however, are 7–8 times lower in the case of Pt compared to that of Au. Tentative interpretation of this effect involves the nature of the Me‐PS bond and the abundance of the respective species. Copyright © 2010 John Wiley & Sons, Ltd.
The Pegase project, a new solid surface probe: focused massive cluster ion beams
Authors: Della‐Negra S. , Arianer J. , Depauw J. , Verkhoturov S. V. , Schweikert E. A. 
Published: June 2010

AbstractThe objective of this project is the development of the SIMS associated to a new probe of the solid: massive clusters consisting of 100–1000 bismuth or gold atoms. The systematic study of the ionic emission intensities as a function of the mass and energy of these projectiles showed that 100–200 qkeV is sufficient energy for the new probe. It is possible to obtain a time of flight (ToF) spectrum with a single impact. These spectra permit to characterize light molecules (MW∼ a few hundreds) with their fragments and intact molecular ion peaks. To analyze the surface, we propose to obtain cluster beams of 100–150 qkeV with a diameter of 10–100 µm, and to associate measurements of time of flight mass spectrometry with the detection of electron emission in order to locate the impact on the surface. We describe the simulation and the installation, on a 130 kV platform, of our column including a LMIS (Liquid Metal ion Source), lenses and Wien Filter, and of a focusing beam line made of an accelerating gap with its shield and a 130 kV insulator. We shall give the experimental beam specifications obtained with the massive cluster ion source Pegase for bismuth and gold. Copyright © 2010 John Wiley & Sons, Ltd.
Cluster primary ion sputtering: correlations in secondary ion intensities in TOF SIMS
Authors: Seah M. P. , Gilmore I. S. 
Published: June 2010

AbstractA brief review is given of some of the behaviors of cluster primary ions in secondary ion mass spectrometry (SIMS). The increased secondary ion yields for cluster primary ions are covered as well as the raised sputtering threshold energies. For organic materials, the increase in intensity as the sputtering yield rises varies with the fragment mass through the spectrum. For Irganox 1010, the intensity of the deprotonated negative and the positive molecular ions increase as the square of the total ion yield. However, the intensity of intermediate fragments increase with a lower power, rising monotonically from unity at m/z ∼400 to 2 at the molecular ion. The constitution of the Irganox 1010 spectra for Ar+, Bi+, Bi$_{3}^{+}$ and Bi$_{5}^{+}$ may be described by a basic spectrum such as that for Ar+ and two further ‘spectra’ which are product terms that multiply the intensity to a power defined by the cluster primary ion species, cluster number and energy. This resolution of the spectra into three components may be translated, for example, to the published data for Si where, for Si$_{t}^{+}$ secondary ion clusters, the terms are very much simpler: one is a constant, the second is a single exponential term dependent of the energy‐deposition density, and the third is related to the cluster‐binding energy. Finally, for studying molecular structure, the use of cluster primary ions in G‐SIMS is outlined. Here, the cluster primary ions are critical for analyzing the weaker, high‐mass peaks. © Crown copyright 2010. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Effects of bias voltage on structure and properties of TiAl‐doped a‐C:H films prepared by magnetron sputtering
Authors: Pang Xianjuan , Hao Junying , Wang Peng , Xia Yanqiu , Liu Weimin 
Published: June 2010

AbstractHydrogenated TiAl‐doped a‐C:H films were deposited on Si substrates by middle frequency magnetron sputtering TiAl target in argon and methane gas mixture atmosphere. Effects of substrate bias voltage on structure and properties of the films, such as the surface morphology, hardness, chemical nature and bond types, were investigated by means of atomic force microscopy (AFM), XPS, Raman spectroscopy and nanoindentation. The friction and wear behaviors of the deposited films were characterized on an UMT‐2MT tribometer. SEM was utilized to analyze the wear scar on steel balls and debris after sliding on the deposited films under dry friction conditions. The results demonstrated that the film deposited at − 100 V exhibited low friction coefficient which is attributed to the easier formation of graphitized transfer layer. Copyright © 2010 John Wiley & Sons, Ltd.
A molecular dynamics study of a 5 keV C60 fullerene impact on a two‐component organic molecular sample
Authors: Ponomarev M. G. , Garrison B. J. , Vickerman J. C. , Webb R. P. 
Published: June 2010

AbstractA study has been made to explore impact‐induced desorption of C60 fullerenes embedded in a benzene matrix as a model of matrix assisted secondary ion mass spectrometry. A fullerene concentration of about 0.5% was incorporated in a coarse‐grained benzene target and then struck by a 5 keV fullerene projectile. The response of the benzene target was compared with a pure benzene target to observe the effects of the embedded molecules on the matrix.Three different trajectories were investigated. In the first, a single sputtered fullerene was ejected joined to a carbon atom from the projectile. In the second, an undamaged C60 was ejected, and in the third, no intact fullerenes were ejected. In all three cases, 4–6 fullerenes were pushed above the initial surface but were relocated into the crater rim, enriching the surface layer with the heavier and more strongly bound component.It is observed that the sputtered fullerenes are ejected with a number of matrix molecules, and that there is a small decrease in the internal energy of the ejected fullerene that corresponds to the gradual separation of the surrounding matrix molecules from the larger molecule. This evaporative cooling may provide a potential benefit to Matrix Assisted SIMS. Copyright © 2010 John Wiley & Sons, Ltd.
Characterizing in situ Glycerophospholipids with SIMS and MALDI Methodologies
Authors: Passarelli M. K. , Winograd N. 
Published: June 2010

AbstractThe dual functionality of a C60+‐Q‐Star hybrid instrument allows for the examination of complex lipid profiles with both MALDI and SIMS methodologies.1 The difficulties associated with characterizing lipids in situ—isobaric interference and salt contamination—are discussed. The inherent advantages of both methodologies were used to deconvolute complex lipid spectra and establish characteristic fragmentation pathways. The high lateral resolution of SIMS allows for single cell images of aplysia californica neurons, while the established protocols were utilized to identify a major lipid component. Copyright © 2010 John Wiley & Sons, Ltd.
Trace metal contamination quantification on Silicon wafers using ToF‐SIMS: RSF determination from deposited droplet standards
Authors: Veillerot M. , Barnes J. P , Danel A. 
Published: June 2010

AbstractToF‐SIMS is now widely used in the microelectronic industry for contamination monitoring of silicon wafers, particularly for metallic elements. However, the accuracy of the technique is still questioned considering the discrepancies, sometimes up to a factor of 10, observable in existing Relative Sensitivity Factors (RSF) databases. A new standard preparation method using intentionally contaminated dried droplets is studied here. It is applied for Na, Fe, Zn and Mo on native oxide silicon wafers. Large‐area analysis (macroraster) is used to image the entire droplet residue of typically several mm in diameter overcoming heterogeneity or droplet movement difficulties. General agreement is obtained with existing data in the literature, however, with disparities still ranging around a factor of two are likely due to top surface ionization unsteadiness. Copyright © 2010 John Wiley & Sons, Ltd.
Analyses of the surfaces of concrete by Raman and FT‐IR spectroscopies: comparative study of hardened samples after demoulding and after organic post‐treatment
Authors: Chollet M. , Horgnies M. 
Published: June 2010

AbstractConcrete surfaces were studied by two spectroscopic techniques, FT‐IR (in ATR mode) and Raman, to establish a nondestructive method to analyze the distribution of hydrated and organic phases. The surface composition of ordinary clinker, polished concrete, concrete after demoulding, and coated concrete as used in building construction was studied. The clinker's mineral phases and the polished concrete were first analyzed by Raman spectroscopy to determine a spectrum database of the specific phases located on the surface of the concrete. Then, both spectroscopic techniques were used to analyze, directly, the surface of hardened concrete after demoulding. No impact of roughness or porosity was highlighted using Raman spectroscopy; many cementitious, or hydrated phases (alite, belite, tricalcium aluminate, ferrite, portlandite and ettringite) were clearly identified. FT‐IR in ATR mode only identified some hydrated phases: portlandite and CaOSiO2H2O (CSH), but organic residues from the demoulding oil were characterized by this technique. Furthermore, the convenience of using these techniques together was tested by analyzing the composition of concrete surfaces coated by different organic post‐treatments. FT‐IR spectroscopy was useful to identify the main organic groups at the concrete surface, whereas Raman spectroscopy was especially able to characterize the mineral/hydrated phases under a thick post‐treatment layer (constituted of polyester varnish). Due to their own specificities, these complementary techniques should be used together to easily identify all the mineral phases and organic residues/coatings on concrete surfaces. Copyright © 2010 John Wiley & Sons, Ltd.
SIMS analysis of Rb‐doped hollow‐core photonic band‐gap silica fiber using a CAMECA 4550 instrument
Authors: Guryanov G. M. , Slepkov A. D. , Gaeta A. L. , Koch K. W. 
Published: June 2010

AbstractA hollow‐core photonic band‐gap fiber exposed to Rb vapor was studied using quadrupole‐based SIMS. The Rb concentration along 30‐cm fibers was analyzed using a Cs+ beam. Effective charge compensation was obtained in the fiber cross‐section without using any metal coating. A low Rb detection limit of about 6 × 1015 atoms/cm3 was obtained in the silica microstructure region of the fiber. SIMS results revealed variations in the longitudinal distribution of Rb in fibers exposed to different loading conditions. Ion imaging of the fiber cross‐section using a Ga+ beam revealed the confinement of Rb atoms to the microstructured photonic region of the fiber, as opposed to the solid glass cladding. Copyright © 2010 John Wiley & Sons, Ltd.
Working group report of database construction of secondary electron yield
Authors: Nagatomi T. , Goto K. , Shimizu R. 
Published: June 2010

AbstractIn this report, we briefly introduce the plan of activities of the 141st Committee on Microbeam Analysis of Japan Society for the Promotion of Science (JSPS141)‐ a working group (WG) for the database construction of the secondary electron yield (SEY) (JSPS141‐WG‐SEY). The WG is established for the construction of databases of experimentally obtained SEYs and two physical constants to describe secondary electron (SE) emission with the help of Monte Carlo (MC) simulation. We also propose a new technique to measure the SEY of insulator by the charge amplification method. Copyright © 2010 John Wiley & Sons, Ltd.
Single molecule manipulation
Authors: Morgenstern Karina 
Published: June 2010

AbstractThe development of molecular switches on the single molecule level is a major challenge on the path towards incorporating molecules as building units into nanoelectronic circuits. With a scanning tunneling microscope (STM) it is possible to induce chemical reactions on a single molecule basis by electrons tunneling inelastically from the STM tip into a molecule. The method is based on high‐resolution imaging at low temperature (5 K) that allows us to identify different groups within the molecule. Chemical reactions are induced by injecting, selectively, electrons into specific parts of the molecule. The success of the manipulation is visualized in the recorded tunneling current during the manipulation and in STM images taken afterwards. We review, here, isomerization of individual molecules adsorbed on metal surfaces. For chlorobenzene and azobenzene derivatives, the effects of different substitutional groups and different substrates are explored. Copyright © 2010 John Wiley & Sons, Ltd.
Quantification of micro‐area analysis in SIMS
Authors: Seki Setsuko , Tamura Hifumi 
Published: June 2010

AbstractFabricating mesa structures with photolithography has been successful for depth profiling in SIMS for micrometer‐scale areas because it eliminates undesired ions originating from the surroundings of the analysis area. However, when we estimate dopant concentration from the SIMS depth profile for ion‐implanted samples using the mesa fabrication method, it is not appropriate to use a relative sensitivity factor (RSF). As an alternative to this conventional RSF method, the concentration was estimated by applying the Lindhard, Scharff, and Schiott (LSS) theory, that is, the distribution of ions penetrating into a solid are assumed to be described by a Gaussian approximation. We carried out the following process. First, the SIMS depth profile of the dopant ions with high sensitivity and high‐depth resolution for a mesa sample was measured. Second, the ΔRp value, the standard deviation of the projected range, was measured from the depth profile. Then, the peak concentration of the dopant ions was estimated from the formula using the measured ΔRp value mentioned above, assuming that implanting ions in a target material are distributed in a Gaussian distribution. This estimation method is a reasonable and practical way of obtaining dopant concentrations from a depth profile. Copyright © 2010 John Wiley & Sons, Ltd.
Structure and properties of chemically prepared nanographene islands characterized by scanning tunneling microscopy
Authors: Yamamoto Mayu , Obata Seiji , Saiki Koichiro 
Published: June 2010

AbstractSingle‐layer graphene islands with a typical diameter of several nanometers were grown on a Pt (111) substrate. Scanning tunneling microscopy (STM) analysis showed most of islands are hexagonally shaped and the zigzag‐type edge predominates over the armchair‐type edge. The apparent height at the atoms on the zigzag edge is enhanced with respect to the inside atoms for a small sample bias voltage, while such an enhancement was not observed at the atoms on the armchair edge. This result provides an experimental evidence of spatially (at the zigzag edge) and energetically (at the Fermi level) localized edge state in the nanographene islands, which were prepared chemically on Pt (111). Copyright © 2010 John Wiley & Sons, Ltd.
Nondestructive depth‐resolved chemical state analysis of (La,Sr)MnO3 film under high temperature
Authors: Shinoda Kozo , Suzuki Shigeru , Yashiro Keiji , Mizusaki Junichiro , Uruga Tomoya , Tanida Hajime , Toyokawa Hidenori , Terada Yasuko , Takagaki Masafumi 
Published: June 2010

AbstractFluorescence yield (FY) X‐ray absorption spectroscopic experiments with a grazing‐ exit geometry for detection of emitted fluorescence were carried out. The observed XAFS spectra provide the information about depth‐resolved chemical state in the surface layer of film materials through the take‐off angle dependence of the escape depth of the fluorescent X‐ray emitted from the sample. For La1−xSrxMnO3 films which are the oxygen electrode materials of a solid‐oxide fuel cell (SOFC), the Mn K XANES spectra were measured using undulator radiation at BL37XU in SPring‐8 synchrotron radiation facility. The results of the conventional FY‐XAS indicated differences due to distortion of MnO6 caused by different temperature, oxygen partial pressure p(O2) and voltage loading conditions in the spectrum profiles. From the results of the angle‐resolved measurements at 973 K in air, a depth‐dependent variation of the Mn K XANES profile in surface region of the film was observed. Though such depth‐dependence was also measured in case of lower p(O2) or voltage loading conditions at the same temperature, the absorbance proportion of absorbing bands contributing the change was different among the split 1s −>4p transition bands. These results indicate a difference in surface region caused by a difference between the surface and the inside of the film in the chemical potential of oxygen. Copyright © 2010 John Wiley & Sons, Ltd.
Investigating the tarnish and corrosion mechanisms of Chinese gold coins
Authors: Liang Chenghao , Yang Changjiang , Huang Naibao 
Published: June 2010

AbstractIn order to investigate the gold coin's tarnish mechanism, the tarnish and corrosion mechanism on Chinese gold coins was investigated by optical microscopy (OM), scanning electron microscope energy dispersive spectrometry (SEM‐EDS), electron microprobe analysis (EMPA), XPS and X‐ray diffraction (XRD). The results indicated that the tarnish on the gold coin was caused by silver on its surface. The main component of the tarnish stain on the gold coin was silver sulfide and silver sulfate. The stain and the contamination originate from the polishing procedure, which accelerated the tarnish process. Two measures can be taken to prevent the gold coin's tarnish. First, the mintage of gold and silver coins should be separated and, second, a chemical cleaning procedure should be introduced. Copyright © 2010 John Wiley & Sons, Ltd.
Influence of surface roughness on near‐surface depth analysis from X‐ray reflectivity measurements
Authors: Fujii Yoshikazu 
Published: June 2010

AbstractX‐ray reflectometry is a powerful tool for investigations of rough surfaces and interface structures. However, in previous studies, the calculation of the X‐ray reflectivity often show a strange effect where interference effects would increase at a rough surface. Here, we propose that this unexpected result of such calculations of the X‐ray reflectivity originates in a neglect of the effect of a decrease in the intensity of refracted X‐rays due to diffuse scattering at a rough surface and interface. In the present study, we present a new, accurate analysis of the X‐ray reflectivity from a multilayer surface taking into account roughness‐induced diffuse scattering. We calculated the X‐ray reflectivity for the W/Si system using a reduced Fresnel transmission coefficient at a rough surface and interface. The calculated reflectivity using this approach gave a physically reasonable result. A new approach using a reduced Fresnel transmission coefficient at a rough surface and interface allowed us to calculate physically reasonable values of the X‐ray reflectivity. Copyright © 2010 John Wiley & Sons, Ltd.
XPS study on band alignment at PtO‐terminated ZnO(0001) interface
Authors: Kim Taeyoung , Yoshitake Michiko , Yagyu Shinjiro , Nemsak Slavomir , Nagata Takahiro , Chikyow Toyohiro 
Published: June 2010

AbstractThe band alignment at the interface between Pt and O‐terminated ZnO(0001) was investigated by depositing Pt films on ZnO using X‐ray photoelectron spectroscopy and ultra violet photoelectron spectroscopy in an ultrahigh vacuum system. Angle‐resolved X‐ray photoelectron spectroscopy measurement showed the band was bent down by 0.06 eV at the ZnO(0001) surface. The binding energy of Zn 2p doublet shifted toward higher values by 0.37 eV when Pt was deposited on ZnO(0001). The work function of ZnO(0001) was 4.08 eV and the valence band maximum measured by UPS on the clean ZnO(0001) surface was 2.82 eV. As a result, the Schottky barrier height of Pt/ZnO(0001) was 0.72 eV in this experiment. Copyright © 2010 John Wiley & Sons, Ltd.
Construction of a pump‐probe system for observing time‐resolved sum frequency images
Authors: Hien Khuat Thi Thu , Miyauchi Yoshihiro , Mizutani Goro 
Published: June 2010

AbstractWe combined a pump‐probe technique with optical sum frequency microscopy, and demonstrated a time‐resolved SF intensity image observation of an HSi(111) surface in ultrahigh vacuum (UHV) conditions. After pump‐light irradiation of photon energy 2.33 eV, pulse duration ∼30 ps, and the width of the spot ∼304 µm, SF intensity image resonant to the SiH stretching vibration with IR probe wavenumber of 2085 cm−1 was darkened dramatically at 0 ps and then gradually recovered. Nonresonant SF signals with IR probe wavenumber of 2020 cm−1 increased at the probe delay time ∼0 ps, and then decreased with the life time of ∼1 ns. The width of the spatial profile of the nonresonant signal was at a minimum of ∼436 µm at the delay time 26 ps, and then increased to ∼673 µm at 930 ps. The origins of these behaviors of the SF intensity images are discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Experimental and numerical analysis of sum frequency microscopic images of a H‐Si(111) 1 × 1 surface after IR light pulse irradiation
Authors: Miyauchi Y. , Sano H. , Okada J. , Yamashita H. , Mizutani G. 
Published: June 2010

AbstractIn this study, we have observed sum frequency (SF) images of a HSi(111) surface after IR light irradiation of pulse width ∼6 µs, and power from 11 to 13 mJ/pulse. After the IR light pulse irradiation, nonresonant SF signals appeared in the irradiated area. The width of the area emitting the nonresonant SF signal was sensitive to the power of IR light pulses. We compared the profile of the SF signal with that of the calculated hydrogen deficiency by using laser‐induced thermal desorption (LITD) model. The profiles of the calculated hydrogen deficiency were consistent with those of the observed nonresonant SF signal qualitatively. Copyright © 2010 John Wiley & Sons, Ltd.
Ellipsometric analysis of corrosion behavior of 3C magnesium alloy surface touched by simulated sweat
Authors: Zhang Shengtao , Wu Fengjing 
Published: June 2010

AbstractAs an optimum shell material, AZ80 magnesium alloys are widely applied in the 3C (computers, communications and consumer electronics) industries. The case of 3C products corroded by a sweaty hand has been simulated and the corrosion characters have been investigated by ellipsometric technology. Thickness variation of corrosive medium film on a Mg alloy surface was monitored. Surface structure of a corrosion layer was described with a three‐layer optical model (substrate—EMA—Cauchy) and thickness of each layer for different soaking time was obtained by fitting experimental data with the model. The corrosion product films with a refractive index of 1.45–1.62, loose corrosion product layer, can only provide limited protection to the substrate when a Mg alloy surface is corroded by sweat again. Copyright © 2010 John Wiley & Sons, Ltd.