bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crack imaging in alumina: a scanning acoustic microscope study
Authors: Smith G. C. , Gee M. G. 
Published: May 2005

AbstractA scanning acoustic microscope (SAM) operating at 750 MHz has been used to image artificially induced cracks in polycrystalline and single crystal specimens of alumina. Although the resolution of the instrument used in this work, at 1.6m̈m, was not as good as that of an optical microscope, significantly more information about the crack characteristics was revealed acoustically. Cracks of finite width act as scattering points for acoustic waves and thus sources of contrast in the SAM image, even when their width is less than the theoretical spatial resolution. In polycrystalline samples it was found that defocussing the SAM both above and below the focal plane, utilising different regions of the V(z) response, enabled contrast due to grain boundaries, cracks, and individual grains to be distinguished. It was also possible to identify different modes of cracking. For the single crystal samples, distinctive contrast was obtained from both horizontal and vertical sub‐surface cracks within one Rayleigh wavelength of the surface. In most materials, features such as these are not readily detectable by other techniques.
On the use of the quartz crystal microbalance for surface analysis in combination with surface sensitive spectroscopies
Authors: Onsgaard J. , Huang W. , Taglauer E. 
Published: May 2005

AbstractThe quartz crystal microbalance (QCM) has a wide range of applications in surface physics and surface chemistry. We present result obtained by combining the high areal density sensitivety of the QCM with surface sensitive spectroscopies like Auger electron spectroscopy (AES) and ion surface scattering (ISS). One type of experiments deals with measurements of sputtering yield variations during ion profiling of metal‐metal interfaces, situated at the surface of the QCM, as a function of varying surface composition. A new method for online measurements of angular distributions of sputtered particles from a solid surface, by utilizing the QCM's as collectors of the ejected particles, is the subject of the other type of experiment.
On the use of markers and tracers to establish the growth mechanism of alumina scales during high temperature oxidation
Authors: Young E. W. A. , Bishop H. E. , De Wit J. H. W. 
Published: May 2005

AbstractVarious ‘marker methods’ have been applied to study the oxidation mechanism of NiAl and Ni‐15Cr‐24Al‐.3Y from 1170 K to 1370 K. Experiments were performed using noble metal markers. The behaviour of both vacuum deposited noble metals as well as implanted noble metals was studied. Also 18O tracers were used. RBS, 18O(p, α)15N resonance spectrometry and SIMS analysis were performed to investigate the alumina scale composition and the position of the marker after oxidation of alloys. The results show that (at 1170 K) NiAl oxidizes mainly by outward diffusion of Al through the oxide scale. It is also shown that noble metal markers may give misleading results. The oxidation mechanism of Ni‐15Cr‐24Al‐.3Y is much more complex. The oxide scale formed on this alloy contains Ni, Cr and Y‐rich oxide regions. These regions contribute to the apparent overall oxidation mechanism of the alloy.
AEM, XPS and ISS characterization of catalyst modifications during propene oxidation over a supported mixed oxide catalyst
Authors: Kremenić G. , Corberán V. Cortés , Tascón J. M. D. 
Published: May 2005

AbstractThe activity of a (MoFeTeCo) O/SiO2 catalyst for propene partial oxidation increases with time on stream, being accompanied by no noticeable change in selectivity to products. The use of a series of characterization techniques (x‐ray diffraction, SEM, analytical electron microscopy, XPS and ISS) allowed us to conclude that the presence of the same phases in the fresh and used catalysts agrees with the constancy of selectivities, while catalytic activity increase is ascribable to a higher degree of dispersion of the active phases. The advantage of the joint use of characterization techniques with different degrees of accessibility to the sample in study are emphasized.
Analysis of plasma enhanced chemical vapour deposition‐grown Borophosphosilicate glass with a combination of Rutherford backscattering and elastic recoil detection
Authors: Oude Elferink J. B. , Dunselman K. , Evers E. J. , Habraken F. H. P. M. , Van Der Weg W. F. , Holsbrink J. 
Published: May 2005

AbstractIt is shown that with a combination of high energy ion beam methods, Rutherford backscattering spectrometry and elastic recoil detection, the elemental composition of borophosphosilicate glass (SiOpPqBrNsHt) can be determined without reference to an external standard. Both thin (< 100 nm) and thick films can be analysed, provided the latter are homogeneous over the layer thickness. Some results pertinent to the B and P uptake during the deposition are briefly discussed.
AES/EDX studies of reactions in phosphate layers during corrosion
Authors: van Ooij W. J. 
Published: May 2005

AbstractThe interface between paint coatings and phosphated automotive steel was investigated using a combined AES/EDX technique. Delamination of the paint during corrosion in salt spray, scab or filiform conditions was found to be controlled by two factors: 1. transformations in the phosphate crystals leading to partial leaching or complete dissolution, 2. wet adhesion retention of the coating in alkaline conditions. The rate of phosphate attack is retarded if the crystals are treated with Cr(III), Cr(VI) or Pb2+ ions prior to coating.
SIMS depth profiling of Al/Nb multilayer structure using Ne, Ar, Kr and Xe ions and neutral species
Authors: Taylor E. , Blanchard B. , Villegier J. C. 
Published: May 2005

AbstractDepth profiles of Al/Nb multilayer sandwich samples composed of 20 alternating layers (each of 20 Å mean thickness) were obtained by secondary ion mass spectrometry using the Cameca IMS 300. Under bombardment with ions and neutral atoms of Ne, Ar, Kr, and Xe, having energies between 1.5KeV and 5.5 KeV, the effect of the mass and energy of the incident particle on the in‐depth resolution was investigated. The layers were easily visible with atoms of Kr and Xe at 2.0 KeV and 1.5 KeV primary energies while considerable inter‐layer modulations were registered in other cases. An interpretation of the artefacts observed at the beginning and the end of the profiles obtained with 5.5 KeV primary ions was given.
Recent developments in spatially resolved ESCA
Authors: Chaney Robert L. 
Published: May 2005

AbstractESCA (electron spectroscopy for chemical analysis) is a general purpose analytical technique for studying the surface properties of a wide variety of materials and material problems. To meet the widest range of experimental conditions, an ESCA instrument should be easily adaptable to the problem under study. The experimental parameters that must be optimized include: spatial resolution; spectral resolution; spectral purity; sample damage; sample presentation; speed of analysis; depth of analysis; sensitivity.In this paper, we will discuss various concepts used to control these experimental parameters. The discussion will provide an analysis of various methods used to obtain high spatial resolution. Finally, we will describe how to optimize instrument performance for some specific experimental situations.
Chemical and structural characterization of rubber compounds by Auger spectra and imaging
Authors: Lin Sin‐Shong 
Published: May 2005

AbstractThe Auger electron spectroscopic technique combined with the microtome sectioning technique is used to examine the chemical constituents of rubber micro‐structures. This technique together with scanning Auger imaging could be employed to yield gross chemical composition, chemical constituents of micro‐domains, elemental mapping, heterogeneities, as well as the chemical states obtainable from peak lineshape analysis. Furthermore, by chemical contrast, more information concerning the microstructure distributions of rubber matrix could be elucidated.The preparation of the specimen is crucial for the success of the present characterization of the rubber compounds. Frozen rubber is first sectioned into 10 to 20 μm thick slices; these are either mounted on a conductive adhesive tape or under‐coated with noble metal. The sectioned surfaces are analyzed by scanning Auger microscopic imaging for surface morphology and elemental distribution, and by Auger point analysis for chemical compositions and lineshapes.The information obtainable includes:(1) overall chemical composition and homogeneity of rubber,(2) dimensions and distributions of rubber components and agglomerates.(3) chemical forms of particle inclusions and agglomerates, and (4) chemical and topological features of surface irregularities. In this paper, the technique for studying rubber compounds is presented, and essential factors affecting the analysis are described.
Voltage contrast XPS—a novel scheme for spatially resolved XPS studies
Authors: Boland John J. 
Published: May 2005

AbstractA novel scheme is introduced which allows spatially resolved XPS studies to be performed in device applications by taking advantage of the ability to bias the various components of the device. The application of a bias voltage produces a shift in the Fermi level of the biased component and there is a corresponding shift in the binding energy of electrons emitted from this component. In this manner it is possible to discriminate between the XPS signals due to a given element but which originate from different areas of the sample. By analogy with the corresponding biasing scheme employed in SEM studies, this technique has been called Voltage Contrast XPS. To illustrate the capabilities of this technique an application involving a recently proposed integrated thermionic emission device is presented.
Characterization of anodic oxides on 304L stainless steel surfaces
Authors: Gaillard F. , Romand M. , Hocquaux H. , Solomon J. S. 
Published: May 2005

AbstractThe effects of anodization parameters, such as current density, electrolyte concentration, electrolyte temperature, and anodization time on the thickness and composition of the oxides formed on AISI 304L stainless steel anodized in H2SO4K2Cr2O7 were studied by low energy electron induced x‐ray spectroscopy (LEEIXS), glow discharge optical spectroscopy (GDOS), and inert ion sputter profiling in conjunction with Auger electron spectroscopy. The physical and chemical properties of these films were correlated with the results of mechanical tests performed on adhesively bonded structures of the anodized pieces in order to test the feasibility of anodization as a prebond treatment for stainless steel.Anodization in H2SO4K2Cr2O7 produces a Cr(III) enriched 100 nm thick oxide film. The novel technique of LEEIXS was used to characterize the chemical state of chromium while the hydrogen content of the anodic oxide was determined by GDOS.
X‐ray photoelectron spectroscopic and thermogravimetric studies of rhenium oxides supported on silica
Authors: Cimino A. , Gazzoli D. , Inversi M. , Valigi M. 
Published: May 2005

AbstractSilica supported rhenium catalysts, containing up to 14% Re (metal) by weight obtained by impregnation with an ammonium perrhenate solution and dried at 110°C, were studied as prepared and then subjected to heat treatments in air, 3 h, in the temperature range 200–750°C.X‐ray photoelectron spectroscopy (XPS) and thermogravimetry (TG), paralleled by chemical analysis and x‐ray diffraction, were applied to identify the occurrence of an interaction between rhenium species formed by thermal decomposition of NH4ReO4 and silica.The results indicate that a weak interaction exists between the products of decomposition of NH4ReO4 and silica, influencing the morphology of the rhenium oxide formed and the temperature of volatilization.The starting material consists of large NH4ReO4 crystals dispersed in the small Cabosil spheres, in agreement with the XPS results (low I(Re)/I(Si) intensity ratio). By heating in air the Re(VII) oxide, produced by the decomposition of the perrhenate, spreads over the silica, as shown by the rise of I(Re)/I(Si) intensity ratio, and its volatilization is slowed down markedly. The volatilization eventually leads to complete loss of Re at about 750°C. The Re(VII) species formed is not in homogeneous situation as indicated by the broadening of the Re 4f peak. A possible scheme for the interaction with the support is suggested.
Angle‐resolved XPS studies of oxides at NbN, NbC, and Nb surfaces
Authors: Darlinski A. , Halbritter J. 
Published: May 2005

AbstractNbN, NbC and Nb are known to be chemically inert with passivating oxides only solvable in HF acid. Despite Nb2O5 as outermost oxide layer, the oxides of Nb compounds show large differences in thickness and in electronic properties. To quantify the differences, angle‐resolved XPS (ARXPS) measurements have been performed. The simultaneous fitting for different angles and preparations of the Nb, C, N and O XPS lines of the oxides yielded the following stoichiometries and distributions:
Nb2O5 is the outermost oxide layer on NbN, NbC and Nb, followed by:
Nb2N2−xO3+x(x<1) on NbN. Dielectric Nb oxicarbides were not identified for NbC.
Underneath the dielectric metallic oxides NbN1−xOx for NbN, NbC1−xOx for NbC and NbO and NbOx for Nb (x<0.5) occur.
The oxide growth (a)–(c) is not planar; instead, the oxides serrate the metal surface on an nm scale. The serration is strongest for the soft Nb and smallest for the harder compounds NbN and NbC in parallel to the oxidation rate which is slowest for NbC.The improved oxide quality and better quality of tunnel junctions in comparison with Nb is explained by this first identification of oxinitrides and of reduced serration of NbN (NbC). The first identification of Nb(N, C)1−xOx compounds extending into the metals explains, e.g., regions of depressed superconductivity, leakage current and pinning. The fluxoid pinning is enhanced by dielectric oxides existing for sputtered NbN between the grains and thus explaining the superior superconducting properties of granular NbN.
Multilayer thin film thickness determination with variable exit angle ultrasoft x‐ray fluorescence spectrometry
Authors: Scimeca T. , Andermann G. 
Published: May 2005

AbstractA theoretical method for obtaining the thickness of thin multilayer films using variable exit angle ultrasoft x‐ray fluorescence spectroscopy is presented. The theoretical approach is based on calculating the ratio of a film's intensity to either an external or internal bulk standard or to another film's intensity within the same sample. The theoretical depth resolution is also discussed using both ratio methods for Fe, Ni multilayer systems. Using this non‐destructive method, some experimental results are also presented for these multilayers.
He(I) photoelectron studies of liquid surfaces—films of malachite green hydroxide and tetramethyl‐p‐phenylenediamine on hydroxypropionitrile solutions
Authors: Ballard R. E. , Jones J. , Read D. , Inchley A. 
Published: May 2005

AbstractMalachite green hydroxide and tetramethyl‐p‐phenylenediamine from complete films on solutions in hydroxypropionitrile and the He(I) photoelectron spectra of these liquid films are presented. The film of malachite green is shown to be in the covalent form although the ionic form predominates in solution.
Investigation of the sampling volume in secondary ion microanalysis II. Evidence of oxide formation during O implantation in pure elements
Authors: Mai H. , Bauer H.‐D. , KießLing W. 
Published: May 2005

AbstractSpecimen modification in secondary ion microanalysis caused by oxygen primary ion bombardment has been studied for pure elements. The steady‐state primary ion implantation volumes in Al, Si. Fe, Nb, Mo, Ta, and W could be analysed by scanning Auger microanalysis depth profiling, transmission electron microscopy, and electron diffraction imaging. The specimen region modified by the primary ions is found to consist of a metal–oxide phase mixture of various degrees of microcrystallinity, involving amorphous components, too. Whereas chemical state is represented by equilibrium compounds the lattice structure can be of metastable or quasi‐equilibrium configuration.
Segregation of chromium in CoOCr2O3 solid solutions and CoCr2O4 spinel phases studied by SIMS and ESCA
Authors: Sikora I. , Stolze F. , Hirschwald W. 
Published: May 2005

AbstractConcentration profiles of chromium are investigated by SIMS and XPS in single crystals and polycrystalline solid solutions of chromium in CoO and in the CoCr2O4 spinel. Annealing at high temperatures favours Cr segregation if the oxygen partial pressure is low. The extent of segregation is more pronounced in single crystals. The enrichment depth is comparatively large and the enrichment factor increases with decreasing Cr bulk concentrations.
On the use of water in the measurement of solid surface tension
Authors: McGuire Joseph , Swartzel Kenneth R. 
Published: May 2005

AbstractCharacterization of surfaces which undergo biological fluid contact is often aided by contact angle analysis. A comparison of solid surface tension evaluation methods, particularly addressing a sessile drop technique including and excluding water as a diagnostic liquid, and one in which the surface itself is equilibrated with water is reported for four materials. A particular non‐linear relationship between macromolecular deposition and solid surface tension has been observed in our laboratory and elsewhere. This relationship may not be predicted if surface analysis is performed outside an aqueous environment.
Quantitative depth profiling by glow discharge mass spectrometry
Authors: Hall D. J. , Sanderson N. E. 
Published: May 2005

AbstractThe ability of the VG 9000 glow discharge mass spectrometer to perform highly quantitative materials analysis has led to applications of the instrument in the field of depth profiling. The result has been the emergence of a technique that is capable of performing rapid quantitative depth analysis for a wide range of elements to sub ppm detection limits. Preliminary investigations into depth resolution suggest the capability of resolving nanometre scale structures.Quantitation is achieved by direct ratioing of ion beams to that of the matrix: elemental sensitivity factors, determined from standards, vary by less than an order of magnitude across the periodic table, and are relatively matrix independent, so that high accuracy results may be attained without the need for closely matching standards and matrix. A high resolution double‐focusing mass spectrometer affords clear separation of atomic peaks from the majority of the inevitable low level molecular species in the mass spectrum, which would otherwise limit the accuracy of trace element determinations.
Application of reflectance studies to layered samples: SiOx on InSb
Authors: Remond G. , Holloway P. H. , Caye R. , Ruzakowski P. 
Published: May 2005

AbstractSpatially resolved optical micro‐reflectometry in the visible region (from 400 nm to 800 nm) is used to study InSb substrates covered with SiOx (1 < x < 2) films of known thicknesses. Using optical constants (refractive index and extinction coefficient) for uncoated InSb derived from two successive reflectance measurements carried out in air and oil, a model of absorbing films on an absorbing substrate was used to calculate the reflectance. Comparison of measured and calculated reflectances for SiO2 films over InSb demonstrate the validity of the model for an absorbing substrate covered with a homogeneous layer. Optical constants for the SiOx layers are obtained from comparisons between experimental and calculated reflectance curves.
A quantitative surface analytical study of electrochemically‐formed copper oxides by XPS and X‐ray‐induced Auger spectroscopy
Authors: Speckmann H. D. , Haupt S. , Strehblow H.‐H. 
Published: May 2005

AbstractElectrochemically partially‐oxidized Cu specimens are transferred from the electrolyte (pH 13 and 14) within a closed system without air contact to the UHV and examined with XPS especially by interpreting the x‐ray‐induced Auger signal L3MM. The signal was fitted with standard spectra of clean Cu and Cu2O using an approximation by the Gauss/Lorentz curves. The oxide thickness calculated from the intensity ratio of the Cu2O and Cu signal with an appropriate value for the escape depth of the electrons agrees well with the evaluation of the electrochemical data. Angular dependent measurements permit a reliable examination of Cu2O of less than 0.5 monolayers. The water content of the oxide layer deduced from a quantitative evaluation of the O 1s XPS signal decreases with increasing thickness of Cu2O approaching less than 10% for ca. 10 monolayers. The small amount of hydroxide is located at the outmost layer. The growth of an outer CuO film leads to an increase of the hydroxide content to ca. 30%. These studies show that the Cu L3MM Auger signal may be used to evaluate quantitatively the amount of Cu2O.
Depth analysis of electrodeposited iron–nickel and copper–zinc alloy coatings by glow discharge emission spectroscopy
Authors: Teo W. B. , Hirokawa K. 
Published: May 2005

AbstractAlloy coatings of FeNi and CuZn electrodeposited on Cu and Fe substrates were analysed with glow discharge spectrometry (GDS) to determine the coating weights of the alloying elements and the concentration depth profile. The coating weight of each element was determined from the integrated intensity which is the area under the intensity‐time curve of the element. A linear relationship is observed between the GDS integrated intensity and the coating weight indicating that GDS is able to quantify the alloy coating. The depth profile obtained was however not the true depth profile because of the effects of sputter broadening (due to differing sputtering rates between the central portion and the edges) and possibly bombardment‐induced segregation (diffusion of zinc towards surface due to the effects of Ar+ bombardment and surface segregation due to heating of the sample) for the CuZn alloy coatings. The use of references of a series of FeNi and CuZn block samples were considered for the determination of the alloy composition. While it is practical for the FeNi system, it is not for the CuZn system because of the effects of surface segregation and bombardment‐induced segregation.
Application of static SIMS to the study of rubber cross‐linking
Authors: van Ooij W. J. , Nahmias M. , Brown A. 
Published: May 2005

AbstractStatic SIMS has been used to analyze the sulfur cross‐links at the surface of compounded polyisoprene rubbers. Linear relationships were found between the normalized intensities of S1− ions and the total cross‐link densities and between the intensities of the S4− clusters and the percentages of the polysulfidic cross‐links.
Platinum contamination of oxide grown by plasma anodization of gallium arsenide
Authors: Lányi Š. , Pavlyák F. , Pinčik E. 
Published: May 2005

AbstractThe contamination of oxide films caused by sputtering of the cathode (Pt) during the anodization of GaAs in an oxygen plasma was investigated. Platinum was found to accumulate near the surface of the oxide, its concentration decreasing rapidly towards the oxide‐semiconductor interface. No correlation of Pt content with deep level spectra from GaAs could be established. The amount of platinum built into the oxide depends sensitively on growth conditions.