bluuebunny/crossref_metadata_2025_split huggingface dataset:
XPS valence band analysis of plasma–treated polymers
Authors: Foerch R. , Beamson G. , Briggs D. 
Published: May 2005

AbstractThe valence bands (VB) of remote oxygen and remote nitrogen plasma‐treated polyethylene and polypropylene were studied to determine changes in the basic polymer structure. Each of the polymers showed a characteristic valence band profile, which retained much of its original shape after plasma treatment. This has suggested that even though plasma treatment can cause the incorporation of a high proportion of functional groups, significant segments of the original polymer structure remain unchanged within the x‐ray photoelectron spectroscopy (XPS) sampling depth. Angle‐resolved x‐ray photoelectron spectroscopy (ARXPS) suggests that near the outer surface, the polyethylene structure is modified by branching and cross‐linking.
Effect of different cooling rates on Cr segregation and determination of the equilibration time of Cr segregation in CoOCr2O3 and NiOCr2O3 solid solutions
Authors: Hirschwald W. , Stolze F. , Sikora I. 
Published: May 2005

AbstractCoO and NiO single crystals doped with chromium were either quenched or slowly cooled after 1 week of annealing at 1150° C and 1200° C in argon. SIMS analysis of the Cr surface distribution revealed a remarkably high Cr concentration in the near‐surface layers of slowly cooled samples and a much smaller concentration for the quenched crystals. The differences of surface Cr concentration in various quenching procedures are also shown.By applying subequilibrium annealing times, different Cr segregation levels and varying thicknesses of surface layers could be established. The time of annealing necessary to obtain equilibrium of segregation was determined for both solid solutions.
Surface modifications introduced to a polytetrafluorethylene‐filled polycarbonate compound by dry sliding against steel as revealed by imaging XPS
Authors: Fletcher I. W. , Davies M. , Briggs D. 
Published: May 2005

AbstractImaging XPS has been used to study surface modifications in a polytetrafluoroethylene (PTFE)‐filled polycarbonate compound as a result of dry sliding wear testing. The novel observation of the formation of a PTFE film over the polymer compound surface (in addition to a transfer film on the steel counterface) will be of significance to the understanding of friction and wear mechanisms and to the performance of polymer systems in tribological applications.
The determination of uncertainties in quantitative XPS/AES and its impact on data acquisition strategy
Authors: Harrison K. , Hazell L. B. 
Published: May 2005

AbstractThe accuracy of quantified XPS/AES compositions for a given sample depends on both systematic and random errors. Parameters such as escape depths, transmission functions, sensitivity factors and whether the model of the surface physical structure used in the quantification procedure is appropriate contribute systematic errors to the quantification. Random errors arise from the Poisson statistics of electron detection. However, in many applications of practical interest, where comparison between samples is the preferred approach to problem solving, precision is more important than accuracy. In such cases, the systematic errors are very similar and the random errors arising from the Poisson statistics of electron detection dominate the problem‐solving exercise. The raw spectra should be capable of providing sufficient precision in the quantified elemental compositions so that the comparison can be made with statistical confidence. This is a particular problem where the elements of interest are present at low levels and there is concern over sample degradation.This paper derives routines to determine the precision (arising from the Poisson counting statistics) in single intensity, peak height, peak area and quantified composition measurements for any acquired spectra, revealing some counter‐intuitive results. The beneficial effects of smoothing and background averaging are also considered. The knowledge is used to suggest novel spectral acquisition strategies to be implemented on data systems, and how they may be optimized when a result to a desired precision is required.
An Electron Spectroscopic Investigation of Attenuation Lengths of Electrons in SiO2 in the Energy Range 450 eV ≤ Ekin ≤ 3100 eV
Authors: Ebel H. , Ebel M. F. , Svagera R. , Hofmann A. 
Published: May 2005

AbstractAn experimental determination of the attenuation lengths of electrons in SiO2 by means of XPS and x‐ray‐excited Auger electron spectra gave a remarkable agreement with recently published inelastic mean free path data.
Determination of the distribution of molybdenum oxidation states in reduced Mo/TiO2 catalysts by factor analysis and curve fitting
Authors: Fiedor Joseph N. , Proctor Andrew , Houalla Marwan , Hercules David M. 
Published: May 2005

AbstractThis study shows that principal component analysis (PCA) in conjunction with iterative target transformation factor analysis (ITTFA) is able to provide an independent estimate of the number, position and, to a certain extent, the shape of spectral components required to describe the Mo 3d envelope as monitored by XPS in reduced Mo/TiO2 catalysts. Three components were required to reproduce the original data.Abstract components from PCA were transformed through ITTFA into components which have spectroscopic meaning. ITTFA was able to predict the position and basic shape of the three spectral components and thus give an estimate of their relative contribution to each spectrum. The three spectral components were attributed to Mo6+, Mo5+ and Mo4+. These factor analysis (FA) results were used in conjunction with non‐linear least‐squares curve fitting (NLLSCF), to provide a detailed description of the Mo 3d envelope during reduction of the Mo/TiO2 catalysts.
XPS Study of hydroxylated oxide layer formation on pure iron and their acid–base properties
Authors: Kurbatov G. , Darque‐Ceretti E. , Aucouturier M. 
Published: May 2005

AbstractX‐ray photoelectron spectroscopy was used to study the hydroxylated oxide layer formation on pure iron and their acid‐base properties. Eighteen samples prepared ex situ were examined. A model of hydroxylated oxide multilayer structure formation and quantification of its composition were proposed. An assumption on the formation of different hydroxyl group species was made.X‐ray photoelectron spectroscopy analysis and ion exchange experiments at the sample surface in solution containing K+ at different values of pH were used for estimation of acid‐base properties.
Porcelain bonding on Ti: Its dependence on surface roughness, firing time and vacuum level
Authors: Hautaniemi J. A. , Juhanoja J. T. , Herø H. 
Published: May 2005

AbstractAdherence of porcelain on titanium and possible bonding mechanisms were studied. The main variables were surface roughness. The bond strength for Al2O3‐blasted rough surfaces was superior to those ground by SiC paper or polished. The fracture was partly cohesive for the Al2O3‐blasted surfaces as a result of mechanical interlocking. For smoother surfaces fracture occurred adhesively. Increased firing time and reduced vacuum level decreased the bond strength when mechanical interlocking was weak. This was most likely related to poor adherence of the interfacial oxide layer to the titanium substrate.
Dimerization of polystyrene during static SIMS measurements
Authors: Licciardello Antonino , Pignataro Salvatore , Leute Angelika , Benninghoven Alfred 
Published: May 2005

AbstractIn this work we report on the results of some static time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) experiments performed on low‐molecular‐weight narrow distribution polystyrene. Evidence of cross‐linking during analysis is found, as indicated by the presence of peaks corresponding to molecules formed by linking of two initial polymer chains. The effect, which can be easily taken into account, does not appreciably affect the molecular weight distribution parameters obtained. However, the observed phenomenon gives the indication that, at least in the case of particularly sensitive systems, ion beam‐induced modification can occur also in static SIMS experiments. In addition, the observed phenomenon can be of relevance in modelling the sputtering of large molecules.
Depth profiling with sample rotation: Capabilities and limitations
Authors: Hofmann S. , Zalar A. 
Published: May 2005

AbstractDepth profiling with sample rotation has become a frequently applied method to obtain the in‐depth distribution of composition in thin films with high resolution. Sample rotation strongly diminishes the effect of local variations of the ion beam intensity and of the sputtering yield, which are the main cause of increasing surface roughness during sputtering and therefore of profile broadening. Capabilities and limitations of rotational profiling are considered with respect to its dependence on various parameters, such as inhomogeneity of the ion beam instensity, ion incidence angle and rotation speed. In particular, it is shown that non‐linear components and excentric movement of the sample lead to periodic features in the profile and to non‐vanishing degradation of depth resolution with depth. For smooth sample surfaces, depth resolution improves with increasing ion incidence angle but is much less pronounced, as for profiling with stationary samples. For originally rough surfaces, the deterioration of depth resolution with increasing ion incidence angle is considerably reduced. The key parameter for optimized conditions in rotational profiling is the ratio of sputtering rate and rotation speed. The minimum necessary, useful rotation speed depends on this ratio and on the magnitude of other contributions to the depth resolution that are not affected by sample rotation.
Electrochemical, ellipsometrical and surface analytical investigations of passive layers on binary Fe/Al alloys
Authors: Schaepers Dirk , Strehblow Hans‐Henning , Künzelmann Ulrich , Schwarz Yvonne 
Published: May 2005

AbstractX‐ray photoelectron spectroscopy, ISS, ellipsometry, electrochemical impedance spectroscopy and electrochemical methods have been used to investigate the passive layers (PAL) on iron/aluminium alloys with low contents of Al (2 up to 12 wt.%). Ellipsometric measurements were performed during the galvanostatic reduction of PAL formed on Fe/8Al in 0.5 M Na2SO4/H2SO4 (pH 3.85) at various potentials. Combining the results of ellipsometric singlelayer model evaluations and of the electrochemical reduction curves it was found that the outer part of the PAL mainly consists of the relatively stable γ‐Fe2O3. Its fraction to the overall thickness of the PAL gives a maximum value when the alloy is passivated at +1 VSHE. At higher potentials, porous films with both decreasing capacities and polarization resistances, measured by impedance spectroscopy, are formed. The XPS and ISS sputter depth profiles of PAL on Fe4/12Al formed in phthalate buffer (pH 5) at +1 VSHE showed an Al enrichment in the centre of the layers. The reductive dissolution of the passive layer in close combination with XPS analysis at distinct states of this process yields similar depth profiles. These results suggest the formation of mixed Fe/Al oxides or oxide compounds.
Development and practical application of a transmission x‐ray photoelectron spectrometer
Authors: Jenkins S. N. , Castle J. E. 
Published: May 2005

AbstractThere is an increasing demand to obtain XPS analyses from smaller sample areas. The development of a transmission x‐ray photoelectron spectrometer will allow spectrum acquisition and imaging with a lateral resolution of approaching 1 μm2. The principle is based on back‐foil excitation where thin samples were placed on an aluminium foil. Electron irradiation of the foil produced x‐rays locally and this, in turn, gave rise to a small source of photoelectrons from the opposite side of the sample. Rastering the electron beam scanned the x‐ray interaction volume, which allowed imaging. Photoelectron lateral resolution was dependent on the sample and foil thicknesses and was determined by the x‐ray excitation volume.In this work a VG Scientific MA500 was modified to give the ideal 180° geometry for transmission x‐ray photoelectron spectroscopy (TXPS). A hemispherical analyser with an extended high‐magnification transfer lens ensured a large solid angle of photoelectron collection and the hemispherical analyser gave the, previously unobtainable, energy resolution necessary to obtain chemical state information. Certain aspects unique to TXPS and image interpretation are described, following discussions of spectral interpretation in the previous paper.It is believed that the local production of x‐rays by a scanning electron beam is the ideal way to examine the ultramicrotomed sections through interfaces and soft composite materials. Harder materials, such as ceramics and metals, require ion beam thinning in a similar way to transmission electron microscopy specimens. A magnesium–aluminium alloy is ion beam thinned to demonstrate TXPS from a harder material. The interlayer between a chlorine‐containing latex and mild steel is also analysed by TXPS following the removal of the bulk substrate and ultramicrotomy. This illustrated the applications in adhesion science, sample stability under analysis and localization of point analyses.
ToF SIMS study of the desorption of emulsifiers from polystyrene latexes
Authors: Weng L. T. , Bertrand P. , Stone‐Masui J. H. , Stone W. E. E. 
Published: May 2005

AbstractThe desorption of emulsifiers from the particle surface of polystyrene latexes prepared by emulsion polymerization has been studied by Time‐of‐Flight Secondary Ion Mass Spectrometry (ToF SIMS). Two polystyrene latexes prepared with respectively sodium dodecyl sulphate and sodium dodecylbenzene sulphonate as emulsifiers were compared. It has been shown that the quasi‐molecular, parent ions and the characteristic fragments of the emulsifiers can easily be observed in positive and negative ToF SIMS. But these ions are more sensitive in the negative mode. The results have shown that after extensive purification with mixed‐bed ion‐exchange resins, the emulsifier was totally absent on the latex prepared with sodium dodecyl sulphate and that only traces of the emulsifier exist on the latex prepared with sodium dodecylbenzene sulphonate. These results suggest that strong acid emulsifiers can be desorbed by mixed‐bed ion‐exchange resins.
Surface chemical changes in PVD TiN layers induced by ion bombardment
Authors: Bertóti I. , Mohai M. , Sullivan J. L. , Saied S. O. 
Published: May 2005

AbstractTiN layers produced by the PVD method were subjected to bombardment by different ion species applied in sequence. The relative atomic concentration and the chemical states of the elements in the surface layer were determined by means of x‐ray photoelectron spectroscopy. The composition and chemical states of a reference sample after wet chemical etching were taken to be representative for the stoichiometric TiN not affected by ion sputtering. For this sample characteristic line energies of Ti 2p3/2 = 454.7 eV and N 1s = 396.7 eV were found. Alternate bombardment with Ar+, N2O+ ions (1–5 keV) results in significant compositional and chemical state changes. Ar+ bombardment leads to preferential loss of N from the outermost (1–3 nm) surface layers of the nearly stoichiometric TiNx (x = 1.0–1.1) without observable changes in the chemical state of the constituents. Bombardment with N2+ ions leads to a build‐up of excess N (x ≫ 1) followed by the appearance of new N 1s and Ti 2p lines at 395.8 ± 0.3 eV and at 456.3 ± 0.3 eV, respectively. N2O+ bombardment increases the O and decreases the N concentration together with a concomitant shot out of a Ti 2p3/2 component peak at about 457.6 eV assignable to Ti2O3.
New spectrometric method for determination of sputtering parameters in glow discharge plasmas—use of helium matrix plasma gas
Authors: Wagatsuma Kazuaki , Hirokawa Kichinosuke 
Published: May 2005

AbstractIn Grimm‐type glow discharge spectrometry, a simple experimental method employing a helium–matrix plasma gas containing several per cent argon is developed to estimate the sputtering yield ratio of the constituents in single‐phase binary alloys. Whereas the voltage–current characteristics of the pure argon plasma strongly depend upon the kind of cathode material, those of the plasma using the mixture gas are almost the same, independent of the alloy composition of the samples. Emission spectra from this plasma source can be excited under similar excitation conditions and thus the observed emission intensities are determined principally by the number of sputtered atoms entering the plasma. The sputtering yield ratios in copper–nickel and nickel–cobalt binary alloys are estimated from analysing variations in the emission intensities with the alloy compositions. The yield ratios obtained correspond well with the values reported in previous works.
Hydrogen content of C60 fullerenes, measured by elastic recoil detection
Authors: Brandstötter A. , Benka O. , Palmetshofer L. , Steinbauer E. , Kastner J. 
Published: May 2005

AbstractThe hydrogen content of thin films of C60 fullerenes, measured by elastic recoil detection (ERD), is investigated. In ERD analysis a new method for particle identification is employed using the ion‐induced electron emission from thin carbon foils. Since the electron emission yield depends on the nuclear charge of the penetrating particle, recoiled H ions and scattered He projectiles can be separated. The reliability and the sensitivity of the technique were checked by analysing a series of ion‐implanted H profiles in silicon. The sensitivity is better than 0.1 at.% H. In as‐grown fullerene films a hydrogen content of about 3 at.% has been found throughout the film. After doping of the fullerene films by ion implantation of K the hydrogen content increased up to 6 at.% in the implanted region.
The influence of Al oxidation on the Cu/Al2O3 interface formation: An XPS study
Authors: Ciampi S. , Di Castro V. 
Published: May 2005

AbstractThe formation of Cu/Al2O3 interfaces at room temperature on aluminium polycristalline samples oxidized in different ways has been studied by XPS. We have compared the growth of copper on samples oxidized by O2, H2O and air respectively. In all the analysed systems an initial oxidation of copper to Cu(I) and a good dispersion of the deposited metal is observed, followed by copper clusters formation. The sample oxidized in air shows a better dispersion of the metal and needs a larger amount of copper to reach the bulk copper spectra.
Optical second harmonic generation as a crystalline surface symmetry probe for III–V semiconductors
Authors: Kravetsky I. V. , Kulyuk L. L. 
Published: May 2005

AbstractA simple way of calculating the second harmonic (SH) rotational anisotropy (the dependence of SH intensity on the sample rotation angle about its surface normal) for arbitrary oriented surfaces of the 43m crystals (e.g. III–V semiconductors) is described. Second harmonic generation (SHG) reflected from (001), (111), (110) and vicinal (001) surfaces of InP and GaAs single crystals was experimentally studied. It is shown that surface crystallographic orientation of the reflecting surfaces leads to a very pronounced effect on the rotational anisotropy and intensity of the SHG from these surfaces. A good agreement between calculated and experimental SH dependences is observed.
Internal analyser inelastic scattering effects in XPS quantitative analysis
Authors: Battistoni C. , Mattogno G. , Righini G. 
Published: May 2005

AbstractThe shape of spectrum in XPS depends on processes in the sample and on the properties of measurements systems. Noise, electron energy analyser resolution, electron inelastic scattering in the sample and analyser, and non‐monochromatic radiation produce a quality reduction of spectrum for quantitative analysis. The undesired scattering of electrons on the outer hemisphere of the analyser or into the lens system leads to spectral background shape distortion and difficulties in the analysis of intensity transmission and resolution functions. A new mathematic procedure, based on deconvolution method, for evaluation and removing instrumental artefact is proposed.
Preparation and characterization of cubic boron nitride and metal boron nitride films*
Authors: Gissler W. 
Published: May 2005

AbstractBoron nitride has generated much scientific interest due to the outstanding material properties of its cubic modification (c‐BN) which can be compared with those of diamond, and to its metal (M) boron nitride compounds (MBN) which have extraordinary mechanical properties such as high hardness and high elasticity. This paper compares and discusses both of these thin film materials, concentrating in particular on their preparation and their mechanical properties in view of future applications as wear‐resistant coatings.There is a strong indication that the mechanism of c‐BN film formation by commonly used physical vapour deposition (PVD) methods is based on recoil implantation of surface atoms into deeper layers. This process creates considerable compressive stress compromising the production of technologically valuable coatings of c‐BN composition. On the other hand BN‐based transition metal films can be made as hard as or even harder than c‐BN films if suitable preparation methods are applied which promote nanometric grain sizes and a mixed phase composition. This paper discusses: (1) Ti implantation into hexagonal BN layers; and (2) co‐sputter deposition from a Ti and Hf target, respectively, and from a BN target; and (3) Ti/BN multilayer interdiffusion. MBN films show good adhesion to metallic substrates such as HSS steels, and preliminary wear tests with a pin‐on‐disk tribometer indicate promising characteristics.Bonding and chemical composition of the films were investigated by electron spectroscopy for chemical analysis (ESCA)‐Auger spectroscopy, the structure and crystallite size by glancing angle x‐ray diffractometry, and the hardness and elasticity by the nanoindentation technique.
Replacement of heavy metal containing pigments in PVC
Authors: Graff John , Osmer Dennis 
Published: May 2005

AbstractMany companies are facing the challenge of replacing heavy metal containing pigments in their products because of possible legal restrictions as well as toxicological and environmental considerations. Replacing one pigment in a single formulation is not generally an insurmountable problem, but replacing this pigment in hundreds or perhaps thousands of formulations might generate some anxiety. The purpose of this paper is to review some of the techniques useful for pigment selection. Colorimetric properties and physical characteristics form the basis for logical selection. Chromaticity characteristics, data on relative opacity, migration resistance, hat and light stability of more than thirty pigments will be included. Examples of the use of the techniques illustrating the replacement of chromate pigments in five colors will be presented. Comparative performance data will be included. On the basis of the information presented, limitations in making high chroma yellow will be discussed.