bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applications of tandem quadrupole mass spectrometry in SIMS
Authors: Leggett G. J. , Vickerman J. C. , Briggs D. 
Published: May 2005

AbstractTandem SIMS studies have been carried out for three polymers—PET, PTFE and LDPE. A variety of collision target gases has been compared and their effectiveness in the construction of fragmentation patterns is considered. For PTFE clusters, xenon provided the most extensive fragmentation patterns, whilst for LPDE clusters, oxygen was preferred. Oxygen and sulphur hexafluoride proved quite reactive when employed with PTFE cluster ions. Using daughter ion and neutral loss data, extensive fragmentation patterns could be constructed.
Microanalysis of inclusion/matrix interfaces in weld metals
Authors: Es‐Souni M. , Beaven P. A. 
Published: May 2005

AbstractThe effects of non‐metallic inclusions on the microstructure of as‐deposited C–Mn weld metals have been investigated in a series of welds produced using different electrode coatings to obtain inclusions of different chemical compositions. The inclusions were analysed on carbon extraction replicas or in thin foils in a 120 kV (scanning) transmission electron microscope (TEM (STEM)) equipped with energy dispersive x‐ray microanalysis facilities. Both x‐ray microanalysis and convergent beam diffraction techniques, with probe sizes down to 10 nm, were used to characterize the inclusions and the inclusion/matrix interfaces.It was found that the ‘cores’ of the inclusions were mainly oxides, such as MnSiO3 or MnAl2O4. The surfaces of the inclusions were either coated with thin layers of copper sulphide, or mixtures of copper sulphide and titanium carbonitride when both copper and titanium were present as impurities in the welds. Effects of non‐metallic inclusions on weld metal microstructure are discussed with respect to the above‐mentioned coatings and the heterogeneous nucleation of the fine acicular ferrite microconstituent.
The reliability of quantitative analysis with AES
Authors: Yoshihara K. , Shimizu R. , Homma T. , Tokutaka H. , Goto K. , Fujita D. , Kurokawa A. , Ichimura S. , Kurahashi M. , Kudo M. , Hashiguchi Y. , Suzuki T. , Ohmura T. , Soeda F. , Tanaka K. , Tanaka A. , Sekine T. , Shiokawa Y. , Hayashi T. 
Published: May 2005

AbstractThe Japanese VAMAS‐SCA working group is composed of 19 institutes. Three kind of AuCu alloys (Au 75 at.‐%–Cu 25 at.‐%, Au 50 at.‐%–Cu 50 at.‐%, Au 25 at.‐%–Cu 75 at.‐%) were prepared, and these specimens, pure Au and pure Cu were distributed to the members of the VAMAS‐SCA working group. The surface concentrations of these alloys were calculated from the Auger peak amplitudes in two ways. One method used the published relative sensitivity factors, and the other used pure Au and Pure Cu as the standard materials. The mean values of the surface concentrations calculated with the published relative sensitivity factors were almost the same as those calculated with the standard materials. This means that the published relative sensitivity factors are reliable to some extent. The error of the surface concentration calculated with pure Au and pure Cu as the standard materials lay between about 3% and 10%, and that with the relative sensitivity factors lay between about 7% and 20%. The calculated surface concentrations of Au were larger than the bulk concentrations of Au when the matrix effect was neglected.
Influence of the inelastic background on the accuracy of factor analysis of electron spectra
Authors: Jansson C. , Tougaard S. 
Published: May 2005

AbstractThe role of the inelastic background in factor analysis of electron spectra is investigated. Ten sets of model spectra originating from different types of in‐depth profiles were considered. Since the background depends on the in‐depth concentration profile, it will normally vary strongly within a set of spectra. In spite of this, it is shown that the background does not give rise to any additional components in factor analysis because it does not vary as a linear spectral component. The inelastic background thus will be projected on the secondary factors in the same way as spectral noise. This and the fact that the background is a smooth function of energy explains why differentiation is an acceptable procedure for background removal when factor analysis is used to identify the relative components of spectral features. Background subtraction is found to be superior to spectral differentiation for those depth profiles where valid algorithms for background subtraction have been developed.
An XPS study of Cs2Te photocathode materials
Authors: Soriano L. , Galan L. , Rueda F. 
Published: May 2005

AbstractThe caesiation of a clean Te metal film during the formation process of a Cs2Te photocathode has been studied by X‐ray photoelectron and Auger electron spectroscopies. Cs2Te is essentially an ionic compound that is stable with a large Cs excess. The ionicity increases with Cs content up to the stoichiometric composition. The Cs excess, which affects the photoemissive spectral response, cannot be reversed by Te deposition since very stable elemental Te clusters seem to be formed. CsTe has been found also during the formation process.
XPS and UPS examinations of Fe53Ni and Fe10Ni in 1 M NaOH and 0.005 M H2SO4
Authors: Hoppe H.‐W. , Strehblow H.‐H. 
Published: May 2005

AbstractThe formation of passive films as a function of time and potential on Fe53Ni in 1 M NaOH in 0.005 M H2SO4 + 0.495 M K2SO4 and on Fe10Ni in 1 M NaOH was studied by XPS. In order to avoid air oxidation and to minimize contamination of the samples, an electrochemical specimen preparation and transsfer system attached to the ultrahigh vacuum (UHV) system was used. Quantitative evaluation of the data yields the total thickness and the composition of passive layers. Characteristic changes of the spectra in the transpassive range for Fe53Ni in the alkaline electrolyte, which include a shift of the peaks of the oxide components to lower binding energies, are observed. They are interpreted as a decrease of the Fermi level towards the valence bend as the result of the oxidation of Ni (OH)2 to NiOOH. This is supported by UPS measurements in dependence of the passivation potential of the specimen, which show an increase in work function corresponding to the Fermi level shift.
The kinetics of oxide film growth on Maraging steel as described by space‐charge effects
Authors: Greyling C. J. , Kotzé I. A. , Viljoen P. E. 
Published: May 2005

AbstractThe oxidation kinetics of a grade 300 maraging steel in air at temperatures ranging from 300 to 600 °C have been determined using Auger electron spectroscopy in conjunction with argon ion sputtering. A limited‐thickness type of growth was observed up to the relatively high temperature of 480 °C. Above 480 °C, the kinetics were parabolic.A thin gold layer sputtered onto the surface before oxidation resulted to a change in the kinetics from limited‐thickness to approximately parabolic growth at temperatures below 480 °C, while it remained parabolic above 480°C.The limited‐thickness oxide growth is described in terms of space‐charge effects, as outlined by the theory of Formhold. The insulating properties of a thin mixed spinel oxide present at the metaloxide interface is critical in bringing about the space charge in the oxide. A change in the electrical conductivity of the mixed spinel is associated with a change in the oxidation kinetics.
AES depth profiling of passive overlayers formed on nickel alloys
Authors: Lorang G. , Jallerat N. , Quang K. Vu , Langeron J.‐P. 
Published: May 2005

AbstractDepth profiling analysis of passive films grown on the surface of two nickel‐based alloys (Inconel 600 and Hastelloy C4) in NaCl media was carried out using Auger electron spectroscopy (AES) and ion sputtering. Improvement to the sequential sputtering model of Hofmann (1976) should be performed when preferential sputtering occurs, especially in Mo‐containing alloys. In this way, the kinetic model of preferential sputtering of Ho et al. (1976) was extended to the case of ternary alloys. However, concentration gradients created by the electrochemical treatment in the metallic layers below the oxidized film make it unsuitable. Passive layers (5–11 monolayers) mainly consist of chromium oxide, always located at the film–alloy interface. A layered depth distribution of oxidized species is generally observed: in Inconel, chromium oxide is successively covered with iron and nickel oxides; in Hastelloy, chromium oxide is covered with nickel oxide (only very few molybdenum atoms are depicted in these films). Increasing the passivation potential, the temperature or the NaCl concentration slightly enhances the nickel oxide amounts in the film, its thickness and the external chloride contents.
Surface characterization of Cux/2Cd1−xIn2+x/2S4 model catalysts
Authors: Moretti G. , Anichini A. , Fierro G. , Lo Jacono M. , Porta P. 
Published: May 2005

AbstractThe sulphospinels reported in the title, with x ranging from 0 to 1.0, were characterized by bulk and surface techniques (XRD, magnetic susceptibility, reflectance spectroscopy and XPS, including x‐ray induced Auger spectroscopy).Homogeneous spinel solid solutions are formed up to x = 0.4, whereas for the other compositions the CuInS2 phase also was indentified by XRD.Only monovalent copper was found in all the samples, in the bulk as well as on the surface.The surface of the sulphospinels is stable to air; on the contrary, the surface of CuS is transformed to Cu2SO4.Making use of the Wagner Auger parameter and of a simple approximation of the shifts observed in the core electron binding energies, we estimate the charge distribution and the electronic environment of the indium ions in the different sites of the spinel structure.
Surface analysis and adhesion of polypropylene after low‐pressure plasma treatment
Authors: Nowak S. , Haerri H.‐P. , Schlapbach L. , Vogt J. 
Published: May 2005

AbstractWe have used XPS core‐level spectroscopy to study the nature of polypropylene surfaces that were exposed to an rf‐induced low‐pressure plasma. This treatment resulted in enhanced oxidation of the polymer surface, which can be attributed to CO functionalities. This modification of the polymer surface allowed the proparation of adhesive joints with improved strength of the polymerepoxy interface. Langmuir probe techniques were used to characterize the plasma. X‐ray degradation of the plasma‐modified polymer surfaces was observed.
ESCA and SIMS studies of plasma treatments of intraocular lenses
Authors: Brinen J. S. , Greenhouse S. , Pinatti L. 
Published: May 2005

AbstractThe surfaces of polymethylmethacrylate (PMMA) intraocular lenses (IOL) modified by treatment in a plasma containing various fluorine‐containing gases were studied by surface analytical techniques. The hydrophobicity imparted to the lens surface was monitored by water contact angle measurements and the degree of fluorination was determined by XPS measurements.The fluorine chemistry on the surface, monitored by XPS and SIMS, was function of the gas mixture employed in the plasma. SIMS imaging was used to monitor coating homogeneity and demonstrated the fragile nature of the coated surface.
The effect of orientation on ion beam erosion rates in ionic crystals measured by SIMS depth profiling
Authors: Kilner A. M. C. , Kilner J. A. , Elliott J. C. , Cressey G. , Littlewood S. D. 
Published: May 2005

AbstractThere are reports in the literature that crystal orientation is a major source of variation in sputter yields when examining biomineralized tissue material. To examine this further, single crystals of fluorapatite and calcite, both mineralogical analogues, were examined with two different SIMS machines, an Atomika 2000 and a Cameca IMSA4F. Craters were eroded on planes parallel to (0001) and (1010) of both samples for different lengths of time, at different angles and with different primary ion beams. Instruments were operated at a voltge of 10 or 15 kV for Cs+ and O2+, respectively, and a primary beam current of 200 nA. The erosion times were such that all sites were exposed to high fluences of 1018 ions cm−2. For a given experimental geometry and primary ion beam, there wee no discernible differences in erosion rates due to crystal orientation. It is believed that this is due to amorphization of the crystal surface at the target site by site by ion bombardment at high fluences. Therefore, we conclude that crystal orientation is not a significant factor in variation of sputter yield in the materials investigated, and suggest that in biomineralized tissue material the development of surface topography is due to other factors.
The effect of carbonate contaminations on the XPS O 1s band structure in metal oxides
Authors: Stoch J. , Gablankowska‐Kukucz J. 
Published: May 2005

AbstractThe aim of the paper is to give examples of XPS analysis, showing how O 1s bands can be affected by surface carbonates. A proper peak assignment (e.g. to O− OH− species) needs the preliminary determination of a carbonate contribution. Although the samples examined represent Co and La compounds only, the principal conclusions can be extended also to other oxide systems.
Ellipsometric analysis of gallium arsenide surfaces
Authors: Ohlídal Invan , Líbezný Milan 
Published: May 2005

AbstractIn this paper the methods of immersion ellipsometry and multiple angle of incidence ellipsometry are used for analyzing gallium arsenide single crystals covered with very thin oxide layers growing under normal laboratory conditions. The values of all the optical parameters of the system mentioned, i.e. the values of the refractive index and the extinction coefficient of gallium arsenide and the refractive index and the thickness of the native oxide layer, can be determined with good accuracy if the experimental data corresponding to several samples of this system are interpreted together. The thicknesses of the native oxide layers corresponding to these samples analysed together must be mutually different. The method is applied at a wavelength of 632.8nm.
Correction of backscattering effects in the quantification of Auger depth profiles
Authors: Barkshire I. R. , Prutton M. , Skinner D. K. 
Published: May 2005

AbstractThe calculation of surface composition form Auger peak heights requires a knowledge of the matrix effects. These are modifications to the yield of Auger electrons arising from inelastic mean free paths, the Auger backscattering factor and sample density effects. A method for approximating the Auger backscattering factor for films of any thickness and atomic number is described. The method is based upon the assumption that the contribution of backscattered primary electrons to the Auger yield will change in proportion to the change in the electron backscattering coefficient of the film with thickness. The auger backscattering factor so calculated varies smoothly from the value corresponding to the bulk material of the film to that of the substrate. Using known generic equations for bulk backscattering coefficients and factors, a simple algebraic expression is obtained. Comparison with experimental data obtained form both high and low atomic number films yields good agreement for various primary beam energies and angles of incidence.
SIMS study on the composition of FeCr and FeCrMo oxide films
Authors: Mathieu H. J. , Vogel A. , Mischler S. , Landolt D. 
Published: May 2005

AbstractDynamic SIMS (secondary ion mass spectroscopy) has been applied to the study of Fe24Cr and Fe24Cr11Mo model alloys subjected to different polarization conditions in the cathodic and in the passive potential region in a sulphate electrolyte. Positive and negative SIMS was performed with a 5 KeV Ar+ primary ion beam using a quadrupole mass analyzer. Measured depth profiles were evaluated by calculating the signal intensity ratios or different species. The data suggest that the concentration in the surface oxide films is a function of depth. The maximum concentration of chromium oxide is found at a depth of the order of 1 nm. Hydroxide is found at the outer surface only. Comparison with mass spectra measured on FeO and Fe3O4 single crystals suggests that no divalent iron ions are present in the passive films. The usefulness and limits of using SIMS for the analysis of passive films are discussed.
TOF‐SIMS satudies of carbon‐fibre surfaces and carbon‐fibre composite fracture surfaces
Authors: Hearn M. J. , Briggs D. 
Published: May 2005

AbstractThe application of time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) to the investigation of interface interactions in carbon‐fibre composites is discussed. Surface analysis of carbon fibres before and after electrochemical oxidation reveals the dominating effect of molecular contamination of the fibre surface (and hence the importance of processing/handling memory effects) on the spectra obtained. High‐resolution SIMS imaging of carbon fibres is particularly useful for contamination identification and clarification of SEM information. Progress in the development of fractography using TOF‐SIMS imaging is also discussed; the important experimental parameters are defined whilst illustrating their effect with a real‐life example.
The effect of silanes on paint adhesion and sites of failure
Authors: Walker P. 
Published: May 2005

AbstractIt is shown that the exposure of organic coatings to high humidity or water immersion causes a rapid loss of adhesion. The use of organofunctional silanes of the general formula R1—Si(OR)3, where R1 is an amino, epoxide, mercapto, methacryloxy or vinyl group, can materially improve the initial, wet and recovered adhesion of epoxide, urethane and alkyd coatings to mild steel and aluminium substrates when used as pretreatment primers and additives.XPS work on the locus of failure of surface coatings on aluminium substrates indicated that although some local loss of adhesion to the substrate may occur, the predominant mode of failure is cohesive within the paint film. These findings are discussed in the light of current theories.
A simple analysis of local wetting hysteresis on a Wilhelmy plate
Authors: Shanahan M. E. R. 
Published: May 2005

AbstractWetting measurements involving evaluation of the contact angle at the triple line of a solid/liquid/fluid system constitute a valuable means of characterizing solid surfaces. In principle, a given three‐phase system possesses a unique contact angle value but, in practice, hysteresis effects often lead to a range of accessible values. Although this inherent range renders estimation of the mean value more difficult, it is suggested here that knowledge of the intrinsic magnitudes and spatial distribution of heterogeneities on the solid leading to hysteresis may be used to characterize the surface more completely. The Wilhelmy plate technique used in dynamic mode (at low speed) effectively leads to a scan of the solid because of the moving triple line. Slight oscillations or ripples on the average measured force are attributed to locally changing populations of weak heterogeneities. A simple mathematical analysis of the behaviour is presented and applied to model arrays of inhomogeneities. Although the models are too simple for direct application to most real surfaces, it is believed that the basic ideas may be refined for use on practical systems.
Depth profile analysis of an electrodeposited multilayer structure with non‐uniform thickness distribution by glow discharge optical spectroscopy
Authors: Weiss Zdeněk 
Published: May 2005

AbstractAn electrodeposited multiplayer structure consisting of nine alternating layers of copper and nickel was depth profiled by glow discharge emission spectroscopy using a Grimm lamp with an anode tube of internal diameter 4 mm. Depth profiled of the non‐uniform region near the sample edge are reported. Thickness inhomogeneity causes the erosion crater bottom to penetrate through individual layers obliquely, which is the reason for signal response distortion. The dependence of signal response on the thickness gradient is discussed and a formula for the thickness gradient estimation from the depth profiles is proposed.
Effect of short‐chain xanthate on electrostatic interactions and equilibrium thickness of foam films from aqueous solutions of non‐ionic frother
Authors: Manev E. D. , Pugh R. J. 
Published: May 2005

AbstractThe equilibrium thickness of free thin films produced from aqueous solutions of C12(EO)5 surfactant (a model frother) with potassium ethylxanthate—KEX (a model collector)—was studied in a wide range of concentrations (from 10−7 M to 2 × 10−2 M C12(EO)5; up to 10−2 M xanthate).The xanthate was found to behave in a similar way to common electrolytes and upon its addition the equilibrium film thickness was reduced, apparently due to the suppression of the electrostatic repulsion. However, at higher C12(EO)5 concentrations (≥10−5 M) the equilibrium thickness of the film increased relative to the thickness established with simple inorganic electrolytes at the same ionic strenght. This was explained by the negatively charged xanthate interacting with the non‐ionic frother at the interface and causing a build‐up of charge.Higher frother concentrations were necessary to produce non‐rupturing films upon increasing the KEX content. This ‘antifoaming’ effect of the xanthate compliments its influence on the electrostatic interactions in the film.
A new approach for curve‐resolving photoemission peaks in XPS
Authors: Mattogno Giulia , Righini Guido 
Published: May 2005

AbstractA new approach for obtaining photoemission peak areas from XPS spectra at the analytical level is proposed. In standard data handling, background removal is necessary for determining the peak areas in order to obtain the atomic fraction of the elements present on outer layers. It is possible to associate an analytical function to the inelastic scattering background. This new approach uses this analytical function during curve‐fitting proicedures on the first derivative of the raw derivative of the raw spectrum.The systems studied are metallic Pd and PdO in powder form and grown over metallic palladium. The results are in good agreement with theoretical hypothesis.
Composition and structure of ion‐bombardment‐induced growth cones on InP
Authors: Malherbe J. B. , Lakner H. , Gries W. H. 
Published: May 2005

AbstractThe previously reported1,2 effect of low‐energy (several keV) ion bombardment on the surface topography of InP was investigated by scanning transmission electron microscopy. Convergent beam electron diffraction patterns of the surface growth ‘cones’ induced by argon ion bombardment of (100) InP between 7 and 10 keV proved the cones to consist of crystalline InP (and not metallic indium, as has sometimes been claimed). The investigation showed that the irradiated surface region is not rendered completely amorphous but that it recrystallizes from the crystalline/amorphous interface in a columnar growth pattern, often terminating in growth cones protruding above the surface. Weak beam investigations revealed that the overwhelming majority of the cones have the orientation of the substrate. These phenomena were observed at all dose densities from 7 × 1015 to 2 × 1017 cm−2.