bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiation‐induced sample modification in surface analysis: InP as an extreme example
Authors: Gries W. H. 
Published: May 2005

AbstractSpectacular topographical effects on InP resulting from ion and electron irradiation, both separately and simultaneously, at conditions common for surface analysis, are used as an example of drastic sample modification. Previously published observations (which include ion irradiation‐induced on‐surface growth of crystalline ‘stubs’ of InP as well as a strong synergetic response to simultaneous irradiation by ions and electrons) are summarized and the ‘microregion’ model proposed for interpretation of the ion‐induced effects is updated and underpinned by additional evidence. This model suggests that mass transport is initiated and proceeds in subsurface regions rather than on the surface (as has been proposed for impurity‐seeded cone growth). Possible explanations are put forward for the synergetic effect of simultaneous ion and electron irradiation. Various cases of synergetic binary interaction are pointed out.
Quantitative trace analysis of technical materials with solid state mass spectrometry: An analytical strategy for SIMS
Authors: Grasserbauer M. , Stingeder G. , Friedbacher G. , Virag A. 
Published: May 2005

AbstractBased on an evaluation of important solid state mass spectrometric techniques regarding detection power, potential for quantitative analysis and applicability, an analytical strategy for the quantitative analysis of technical materials with high‐performance SIMS that has the broadest applicability of all solid state mass spectrometry techniques is discussed. The major topics dealt with are reduction of random and systematic errors, preparation and characterization of suitable reference materials and assessment of precision and accuracy. It is intended to demonstrate that extensive procedures have to be applied to obtain accurate quantitative results—not only for SIMS but also for the other solid state mass spectrometric techniques.
Electrochemical and second harmonic generation investigation of nickel corrosion in 0.1 M NaOH
Authors: Biwer B. M. , Pellin M. J. , Schauer M. W. , Gruen D. M. 
Published: May 2005

AbstractThe study of metallic corrosion has been hampered in the past by the lack of reliable in situ surface‐sensitive techniques. The application of second harmonic generation (SHG) to the investigation of such problems was demonstrated in earlier work on Fe corrosion. The present study further illustrates the general utility of SHG as a surface probe by extending its use in conjunction with standard electrochemical methods to the study of the Ni electrode in 0.1 M NaOH. The initial Ni oxidation product is shown to be different from that comprising the passive film, which in turn is shown to change over the region in which the electrode exhibits passive behavior. The use of two different laser frequencies for the production of SHG helps one to discriminate between charging and compositional effects in the interpretation of changes in the SHG signal.
Electron‐stimulated desorption of neutrals from 6063 aluminum—velocity distributions detected by 193 nm non‐resonant laser ionization
Authors: Young C. E. , Whitten J. E. , Pellin M. J. , Gruen D. M. , Benbow R. L. , Jones P. L. 
Published: May 2005

AbstractElectron‐stimulated desorption of neutrals from methanol‐dosed 6063 aluminum alloy has been monitored by laser ionization at 193 nm wavelength. Primary electron energies were in the range 1–3 keV. Time‐of‐flight spectra for the neutral desorbate were characterized by a low value of the peak velocity (250 m s−1) and a non‐Boltzmann form of the distribution. Neutral desorption was ascribed to the parent methoxy (CH3O) species, based on mass spectrometry of the laser‐ionization fragmentation pattern as a function of intensity. Ionic desorption was dominated by H+, which was observed to have kinetic energy peaked at ∼3 eV. Approximate estimates of neutral and ion yields were made, based on ion‐optical modeling of apparatus transmission characteristics.
A chemical and morphological study of phosphorylated chrysotile fibres, using FTIR, EPXMA and AAS
Authors: Berghmans P. A. , De Waele J. K. , Philippaerts J. G. , Vasant E. F. , Adams F. C. 
Published: May 2005

AbstractChanges in the surface composition of different chrysotile and chrysophosphate fibres upon leaching in oxalic acid and bidistilled water measured with Fourier transform infrared spectroscopy (FTIR) and electron probe x‐ray microanalysis (EPXMA) are presented. The results are supplemented with data obtained by atomic absorption spectroscopy (AAS) and colorimetry for the measurement of the leached magnesium, iron, phosphorus and chloride in solution. This assists in the elucidation of the potential consequences of fibre surface properties in relation to the carcinogenic potency and biological activity. This study demonstrates the potential of the FTIR and EPXMA techniques for the characterization of natural and physicochemically modified and depleted fibres.
Conversion of Auger sensitivities at one primary excitation energy to those at another
Authors: Sato T. , Nagasawa Y. , Sekine T. , Sakai Y. , Buonaquisti A. D. 
Published: May 2005

AbstractIn Auger electron spectroscopy, the relative sensitivities of elements, which are widely used in quantitative analysis, are primarily obtained by measurement. Nevertheless, it is very tedious to collect all relative elemental sensitivity factors for different primary electron beam energies. In view of this, we have examined methods of deriving the relative sensitivity factor for an arbitrary electron beam energy from one experimental value determined at a set energy. For this calculation, we have to consider the contributions of the ionization cross‐section and the electron backscattering factor. Several formulas for the ionization cross‐section and the backscattering correction factor have been reported. We have performed experiments to examine their correction accuracy. It was found that when Gryziński's formula is used as the ionization cross‐section and Love‐Scott's formula as the backscattering correction factor, the difference between calculated sensitivity values and measured values was found to be <15% for excitation energies of <20 keV.
The characterization of wafer surfaces and interfaces using high‐frequency phonons
Authors: Rani Hamid Bin , Edwards S. C. , Wigmore J. K. , Collins R. A. 
Published: May 2005

AbstractWe show that the scattering of nanosecond heat pulses can be used to characterize the surface quality of single crystal wafers for device applications. The technique is sensitive because the high‐frequency phonons that make up the heat pulses have wavelengths that are comparable with the typical scale of surface imperfection. The advantages of the technique are that it is non‐destructive, can be applied to both semiconductors and insulators, requires minimal preparation and can be used to observe deep subsurface structure.
AES study of palladium overlayers on polycrystalline copper
Authors: Heras J. M. , Viscido L. , Wedler G. , Borgmann D. 
Published: May 2005

AbstractThe growth of Pd layers on polycrystalline Cu substrate at 176 K and 300 K was studied in an Auger system with facilities for photoelectric work function (WF) measurements and automated data acquisition. The LVV and MVV Auger transitions of Cu, as well as the corresponding MVV and NVV of Pd, were monitored in relation to Pd overlayer thickness, annealing temperature and sputtering time. The ‘local’ WF change, determined through the secondaries' cut‐off shift, and the absolute photoelectric WF were also monitored.The initially linear increase in the Pd atom fraction, with only one break during deposition at 300 K, suggests a Stranski–Krastanov film growth mechanism. The simultaneously monitored Auger M23M45M45 Cu doublet at 59–61 eV changes from the very beginning of the Pd deposition into one broadened peak at 61 eV, possibly owing to a roughness effect. With sputtering, the slope of the Pd concentration at the interface decreases when the temperature of deposition and sputtering increases from 176 K to 300 K, indicating diffusion of Pd even at 300 K. By sputtering with Ar+ ions of 5 keV, a depth resolution of ∼3.2 nm was found. Annealing at T > 473 K causes a rapid diffusion of Pd atoms into the Cu substrate.The ‘local’ WF is affected dramatically by Pd deposition and sputtering, while the average photoelectric WF is not as sensitive.
A microbeam analytical study of a‐C: H films
Authors: Fitzgerald A. G. , Henderson A. E. , Storey B. E. 
Published: May 2005

AbstractCarbon films prepared by sputtering, ion beam deposition methods and chemical and physical vapour deposition methods have been studied by a range of microbeam analytical techniques. The presence of hydrogen and hydrocarbon components in these films has been established regardless of whether hydrocarbon gas is used in the deposition process. The α‐carbyne and diamond modifications of carbon have been identified in some of these films. The sensitivity of these carbon films to electron and ion irradiation is discussed. The form of carbon bonding has been investigated by x‐ray photoelectron spectroscopy.
Comparative study of TiNx films deposited by reactive ion beam sputtering at 77 and 300 K
Authors: Buschert R. C. , Gibson P. N. , Gissler W. , Haupt J. , Manara A. , Jiang X. , Reichelt K. 
Published: May 2005

AbstractComparative studies were performed on the chemical composition, the microstructure, residual stress, hardness and Young's modulus of titanium nitride films, which were prepared by reactive ion beam sputtering at substrate temperatures of 77 and 300 K. The main experimental parameter of sample preparation was the N2/Ar gas flow ratio r, which determines not only the chemical composition of the film, [N]/[Ti], but also its mechanical and electrical properties. The chemical composition was investigated by AES, XPS and RBS. Microstructural data were obtained by grazing incidence x‐ray diffractometry. The measurements indicate a mixed phase of Ti, Ti2N and TiN at lower r ratios and of cubic TiN at r > 0.05. From the integrated breadth of the diffraction lines, grain size D and strain ε were determined: 150–250 Å for D and 0.5–1.5% for ε The residual stress was measured by determining the bending of the substrate. Extraordinarily high compressive stress with pronounced maxima around stoichiometric composition was observed. The microhardness Hv and Young's modulus E were derived from the indentation loading–unloading curve, as measured with a nanoindenter. Values up to 25 GPa for Hv and up to 10 GPa for E were obtained.
Temperature dependence of the phosphorus segregation at the twin boundary in an Fe–4 at.% Si alloy
Authors: Lejček P. , Hofmann S. 
Published: May 2005

AbstractAES of in situ fractured bicrystals of an Fe–4 at.% Si alloy containing traces of phosphorus was used to study the temperature dependence of the segregation at the symmetrical {112} (coherent twin) grain boundary between 773 and 1173 K. The observed enrichment of P decreases with temperature, whereas that of Si increases slightly. This behaviour is described by a mutual repulsive interaction coefficient α′ = 92 kJ mol−1 of P and Si and the corre‐sponding pure binary segregation enthalpies ΔH0P = −7.9 kJ mol−1 and ΔH0Si = −3.0 kJ mol−1, the absolute values of which are considerably lower than those reported for polycrystalline samples of FeP and FeSi. The differences are explained on the basis of orientation, concentration and interaction effects.
The effect of hydrogen content on silicon coordination in silicon oxynitrides: An Auger parameter study
Authors: Rivière J. C. , Crossley J. A. A. 
Published: May 2005

AbstractSilicon oxynitride films prepared by plasma‐enhanced chemical vapour deposition (PECVD), with compositions in the range O/N = 0 to O/N = 0.89, and containing amounts of hydrogen in the range H(H + O + N) = 0.07–0.31, have been studied by measurement of the Auger parameter α = EK(Si KLL) – EK(Si 2s). A pure thermal oxide was also included. Depth profiles using 4 keV argon ions showed that the films were uniform in both composition and silicon coordination. Peak widths of the 2p, 2s and KLL features were measured as a function of oxygen fraction O/(H + O + N); in contrast to the films prepared by low‐pressure chemical vapour deposition (LPCVD) studied by Rivière et al., the widths of the 2p and 2s peaks were constant. However, the width of the KLL Auger peak went through a maximum near O/(H + O + N) = 0.5, as observed previously. The 2p and 2s width invariance is interpreted as being due to the presence of hydrogen, in that the weak hydrogen bonding allows strain due to varying bond angles and distances to be taken up more easily than in SiO and SiN bonds. The KLL variation, on the other hand, is suggested as arising from the effect of the core hole in the L shell, causing instantaneous local strain around the ionized Si atom associated with SiO and SiN bonds.The dependence of the Auger parameter on the oxygen fraction O/(H + O + N) was different from that found for the LPCVD films in that it was accurately linear. As a result, the PECVD films do not obey the random bonding model of progressive substitution of N by O, but consist of a mixture of two phases, in agreement with Claassen and Kuiper who suggested the phases SiO2 and Six Ny Hz. The linear decrease in the Auger parameter is thus due to the proportionate decrease in the Six Ny Hz content. Plots of the Auger parameter as a function of (n2 − 1)/n2 were again linear, confirming the direct relationship between the parameter and the polarization energy found previously.
VAMAS surface chemical analysis technical working party—an overview of project objectives, progress and the requirements for further work
Authors: Seah M. P. 
Published: May 2005

AbstractAn update for 1989 is given for the VAMAS Surface Chemical Analysis Technical Working Party. The overall programme now has 26 projects targeted to solve key problems in the enabling base of AES, XPS, SIMS, SNMS and sputter depth profiling. Increased coordination of projects is leading to stronger project databases. Eleven of the projects have involved round robins, and details are provided of results where the analysis is complete and of project leaders where new participants are invited.
A comparison of the composition of thin films on substrates determined by EDX and surface analysis
Authors: Fitzgerald A. G. , Gillies A. D. , Watton H. L. L. 
Published: May 2005

AbstractSingle‐scattering Monte Carlo electron trajectory simulation has been implemented for the calculation of characteristic x‐ray production in thin films on substrates. The validity of the simulation has been verified by comparison with EDX results from various thicknesses of gold and silver films on silicon substrates over a range of electron energies. The simulation has been applied to binary thin films on substrates, and computational methods have been devised to eliminate the lengthy graphical techniques for film thickness and composition determination used previously. A comparison of calculated film compositions has been made with composition obtained by surface analytical techniques.
Determination of the centroid depths of the depth profiles of ion‐implanted analytes by angle‐resolved electron microbeam analysis
Authors: Gries W. H. , Koschig W. 
Published: May 2005

AbstractAngle‐resolved signal ratio electron microbeam analysis (AR/SR/EMA) was applied for the determination of the centroid depth of the ion‐implanted depth profile of 100 keV 1016 cm−2 P in Si. The experiment is part of an investigation on the suitability of AR/SR/EMA for application in the (non‐destructive) calibration of ion‐implanted reference materials.
Characterization by XPS and XAS of supported Pt/TiO2CeO2 catalysts
Authors: Dauscher A , Hilaire L. , Le Normand F. , Müller W. , Maire G. , Vasquez A. 
Published: May 2005

AbstractTiO2 and CeO2 are will known for inducing strong metal‐support interactions J(SMSI) of a different nature when used as supports for Pt catalysts. X‐ray photoelectron spectroscopy analysis of mixtures of TiO2CeO2 oxide supports (80:20 and 20:80) reveals at the surface a remarkable stabilization of cerium in the +3 oxidation state; the stabilization is more pronounced with lower cerium oxide concentration. X‐ray absorption spectroscopy measurements done on the LIII edge show the same variation as a function of cerium oxide concentration, but in the bulk the reduction is much lower. Cerium in Pt/TiO2CeO2 catalysts exhibits the same behaviour.
Application of nuclear methods to the study of transfer wear of PTFE on stainless steel and silicon
Authors: Lappalainen R. , Yang E‐L. , Hirvonen J.‐P. 
Published: May 2005

AbstractIon beam analysis techniques available at a low‐energy accelerator (<2.5 MV) were utilized to study the transfer wear in the sliding contact of three types of PTFE (Teflon) and stainless steel (AISI 316) or silicon. The methods used include nuclear resonance broadening, back‐scattering, deuteron‐induced reactions, forward recoil spectroscopy, etc. These non‐destructive methods were used to probe the main components of the transferred film and the surface impurities with high sensitivity and reasonable depth resolution (a few nm). These complementary nuclear methods give reproducible results without any special sample pretreatment for insulating polymer films that are a few atomic layers thick. With an optimized measuring geometry, the time of measurement required for a typical accuracy of 1% for the transferred amount was reduced to a few minutes.
Nuclear microprobe characterization of surface hardening by precipitation of chromium carbides after laser beam treatment of a NiCr substrate
Authors: Mosbah Michelle , Gosset James , Trocellier Patrick , Puig T. , Cantarel M. , Condat M. 
Published: May 2005

AbstractSurface treatment by laser provides interesting solutions to the problem of accelerated wear of materials. The aim of the present study is the characterization of chromium carbide‐rich surface alloys after laser beam melting of an Ni70Cr30 carbon‐precoated substrate. Transmission electron microscopy investigation shows the structure of the carburized zone, and electron diffraction shows the type of carbides formed. Carbon profiling of the lasered surface was performed by nuclear microprobe using the 12C(d, p0)13C reaction; Ni and Cr (more precisely, the ratio Ni/Cr) were evaluated semi‐quantitatively by means of particle‐induced x‐ray emission. The specificity of the method and the experimental conditions are explained. Wear results are very satisfactory and close to those obtained by injection of chromium carbide powders into the laser beam in the case of a Nimonic alloy: wear rates are divided by two orders of magnitude.
Mixed‐Oxide electrode study by secondary ion mass spectrometry
Authors: Daolio S. , Facchin B. , Pagura C. , De Battisti A. , Battaglin G. 
Published: May 2005

AbstractRecent interest in the study of dimensionally stable electrode anodes by means of analysis techniques opens up possibilities of improving knowledge on the electrocatalytic activity of mixed‐oxide electrodes. In this work we report the SIMS characterization of IrO2/TiO2 coatings by many positive and negative ion species identifications and depth profiles of the most significant species.
Quantitative time‐of‐flight secondary ion mass spectrometry of a perfluorinated polyether
Authors: Fowler David E. , Johnson Roboert D. , Vanleyen Dieter , Benninghoven Alfred 
Published: May 2005

AbstractQuantitative determination of the molecular weight and composition of submicrogram of a perfluorinated polyether (PFPE) supported on Ag and Si substrates was from empirical relationships derived from the intensities of specific high‐mass (≥ 800 amu) fragmentation ions from time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) measurements. These relationships are explained in terms of simple concepts regarding the process of volatilization, fragmentation and ionization in TOF‐SIMS. The results for both negative and positive ions are nearly independent of the substrate materials used, demonstrating that the high‐mass fragmentation ions in TOF‐SIMS may be useful generally for in situ quantitative analysis of PEPEs on non‐specific substrates. This is an important difference between the TOF‐SIMS fragmentation spectrum and the complementary TOF‐SIMS cationized molecular ion spectrum, which requires special sample preparation and/or substrates. In order to interpret the quantitative information available in the TOF‐SIMS fragment spectrum, it was absolutely necessary to characterize extensively the PFPE samples using NMR and TOF‐SIMS Ag+ ‐cationized molecular ion results. This characterization helped to demonstrate the power of TOF‐SIMS to do quantitative analysis and led to additional insight concerning the SIMS ion‐forming process for PFPE. This study represents one of the first attempts to make quantitative use of the high‐mass fragment ion intensities in SIMS studies of polymers, and presents a method for confirming the origin of the mass peaks in the spectra.
Surface modification of extended chain polyethylene fibres to improve adhesion to epoxy and unsaturated polyester resins
Authors: Chappell P. J. C. , Brown J. R. , George G. A. , Willis H. A. 
Published: May 2005

AbstractExtended chain polyethylene fibres have been treated in ammonia and oxygen lo‐pressure gas discharges (plasmas) in order to enhance adhesion to epoxy and unsaturated polyester resins, respectively, and thus significantly improve fibre/resin interfacial properties in fibre‐reinforced polymer composites. Ammonia plasma treatment results in the incorporation of amine functional groups onto the fibre suface. The treated fibre surface has been analysed using XPS and spectrophotometric techniques. Extended chain polyethylene/epoxy composites made from ammonia, plasma‐treated fibres show a marked increase in interlaminar shear strength over composites made from untreated, corona‐treated or oxygen plasma‐treated fibres. The increase in fibre/resin adhesion after ammonia plasma treatment is confirmed by SEM observations of fracture surfaces, which show clean interfacial fracture surfaces in composites made from treated fibres. Fibres modified by oxygen plasma treatment contain a significant concentration of carbon‐oxygen functionalities, which contribute to the polarity of the surface and hence increase wet‐out by unsaturated polyester resins. The concentration and nature of carbon‐oxygen species on the fibre surface have been determined by XPS. Pull‐out tests on multifilament yarns embedded in a polyester resin confirm the high fibre/matrix adhesion achieved with the oxygen plasma‐treated fibres compared to corona‐treated or untreated fibres. Tensile properties of the fibres are reduced significantly after prolonged treatment in an oxygen plasma, while in an ammonia plasma the fibre strength is unaffected.
Quantitative SIMS of III‐V compounds of graded composition without the use of standards
Authors: Crapper M. D. , Chew A. , Bradley R. H. , Sykes D. E. 
Published: May 2005

AbstractA method is proposed for obtaining the matrix element SIMS sensitivity factors for III‐V compounds of the form ABxC1–x without using standards. This method tests for variation of sensitivities with concentration and, in the case where no strong variation is shown, allows determination of the sensitivity functions by use of samples where the concentrations of two elements vary continuously over a wide range. This method provides a no‐standards route to quantification of matrix element concentrations in SIMS depth profiles of layers with graded compositions.