bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depth resolution improvement in AES sputter profiling of Ni/Cr multilayers on rough substrates using two ion beams
Authors: Hofmann S. , Zalar A. 
Published: May 2005

AbstractThree point depth profiling by scanning Auger microscopy and simultaneous sputtering with one ion beam and subsequent addition of a second ion beam, incident from a different direction, is applied to multilayer Ni/Cr structures deposited on a rough (roughness Ra = 2.3 μm) silicon substrate. Depending on the analysed microarea of about 1 μm diameter, depth resolutions between 25 nm and 44 nm at 125 nm sputtered depth were obtained using one ion beam. The extent of the improvement in Δz after sputtering with two ion beams is directly related to the absolute values obtained in each of the three microareas. The results are explained in terms of shadowing and redeposition effects which are diminished by the use of sputtering with two ion guns.
Auger analysis of metal matrix–ceramic fiber composites
Authors: Sherman Robert 
Published: May 2005

AbstractThe mechanical behavior of composite systems is related to the properties and relative contents of their constituents. In certain systems the reaction zone (the interface region between the metal matrix and the ceramic fiber) can have a major role in determining the overall mechanical response of composites. For magnesium and magnesium alloy (ZE41A) metal matrix–aluminum oxide fiber composites, an analysis using Auger spectroscopy of the reaction zone indicated that complex chemical reactions occur during processing and that reaction zone chemistry and structure are important variables in determining the overall mechanical response. The results of the Auger analysis are discussed and compared with other surface analysis studies performed on the same composite system.
Scanning Auger measurements of nickel coated carbon fibers
Authors: Brinen J. S. 
Published: May 2005

AbstractScanning Auger microscopy (SAM) was used to study the chemistry of the interfacial region of nickel coated carbon fibers. The interface is exposed by either in situ fracture or by sputtering with Argon ions. From the fracture experiments it was found that the carbon content on the interior nickel wall is double the carbon content in the bulk nickel suggesting the nickel–carbon interface is stronger than the forces holding the carbon fiber together.
Comparison of Auger and SIMS analysis of a thin passive oxide film on iron—25% chromium
Authors: Mitchell D. F. , Graham M. J. 
Published: May 2005

AbstractA comparison of three surface‐analytical methods, viz: variable escape angle Auger electron spectroscopy, Auger sputter profiling and SIMS sputter profiling, is presented for a 1.8 nm‐thick ‘passive’ oxide film on Fe–25% Cr alloy. The three techniques give identical results regarding the composition of the film as a function of depth. This means that with the proper choice of sputtering conditions (heavy ions of low energy), sputter mixing and sputter reduction are not a problem. It is evident from the experimental data that SIMS sputter profiling has the best depth resolution of the three techniques for such a thin film.
Breakdown voltage and surface compositon in a lead borosilicate glass
Authors: Vasquez Patrizia , Puglisi Orazio , Licciardello Antonino , Arnold George W. , Patti Alfonso , Pignataro Salvatore 
Published: May 2005

AbstractThe breakdown voltage of a lead borosilicate glass used to passivate ‘mesa’‐channels in silicon chips is considerably lowered by the chemical treatments required by the fabrication flow chart. Surface analysis and near‐surface analysis of the glass samples shows that the chemical etching depletes both surface and near‐surface regions of the glass of Al, B and Pb. Contemporaneously the glass surface becomes O‐ and H‐rich with respect to the untreated samples. This is consistent with a mechanism based upon the formation of a silanol‐rich surface which lowers the breakdown voltage.
Ion bombardment effects in the sputtering of single‐ and two‐phase brass alloys; Cu: 18–48% Zn
Authors: Hammer G. E. , Shemenski R. M. 
Published: May 2005

AbstractThe effect of ion bombardment on the near‐surface composition of brass has been investigated over a bulk composition range including single‐phase α (fcc) brass and two‐phase, α + β (bcc) brass. Auger electron spectroscopy has been used to determine the equilibrium near‐surface composition after ion sputtering with argon and xenon at ion energies between 1 and 4 keV. Preferential removal of the zinc was found under all conditions. X‐ray photoelectron spectroscopy has been used to investigate variations in composition in the first atomic layers by comparison of the intensities and escape depths of the 2p and 3p photoemission peaks. The near‐surface composition was primarily a function of ion energy in the single α phase, with higher ion energy increasing the preferential removal of zinc; no change was detected comparing data from information depths of 5 vs. 10 monolayers. In the mixed α + β phase, surface zinc concentration decreased with increasing ion energy and mass, and depletion of zinc was greater nearer to the surface.
Investigation of the sampling volume in secondary ion microanalysis III. Peculiarities of multi‐element metal specimens under oxygen bombardment
Authors: Mai H. 
Published: May 2005

AbstractThe modification caused by oxygen primary ion bombardment in homogeneous multi‐element metal specimens has been studied. Investigations of the appropriate sample region of Fe40Ni40P14B6 and Fe81Si3.5C2B13.5 metallic glasses by transmission electron microscopy, electron diffraction and scanning Auger microanalysis revealed an inhomogeneous steady‐state sampling volume. Chemical decomposition of the initial matrix, precipitation of oxide components and formation of crystalline phases have been proven.
Auger signal‐to‐background ratio for incident beam voltages ranging from 30 keV up to 100 keV
Authors: Chazelas J. , Friederich A. , Cazaux J. 
Published: May 2005

AbstractThe Auger spectra of silver, copper, gold, SiO2 and GaAs have been obtained, for the first time, by using incident beam energies E0 ranging from 30–100 keV. It is found that the signal‐to‐background ratio always increases when E0 is increased, while the signal‐to‐noise ratio slightly decreases. Some consequences related to the use of high primary beam energies in AES are suggested.
Quantifying the effects of uneven etching during the SIMS analysis of periodic doping structures grown by silicon MBE
Authors: McPhail D. S. , Dowsett M. G. , Fox H. , Houghton R. , Leong W. Y. , Parker E. H. C. , Patel G. K. 
Published: May 2005

AbstractProblems associated with the secondary ion mass spectrometry (SIMS) depth profiling of periodic doping structures are discussed with reference to experiments on a boron‐in‐silicon modulation doping structure and a boron‐antimony silicon super‐lattice, both grown by silicon molecular beam epitaxy (MBE). The effects of uneven etching during SIMS analysis are compared with the effects of dopant diffusion during growth. Uneven etching is modelled with an algorithm in which the macrotopography of the crater base is described in terms of an unevenness function f(x, y). Simulation depth profiles involve passing craters of this topography f(x, y) through specified, laterally homogeneous, doping distributions ρp(z) in a series of equal depth interations. The predicted SIMS signal is proportional to the amount of dopant sputtered per depth iteration. The model explains the peak shapes and the loss of depth resolution with depth that are observed experimentally. The effects of dopant diffusion during growth are found by re‐heating parts of the wafer to the growth temperature for various periods of time and then SIMS depth profiling them (thermal cycling).
Investigation of solidsolid surface adsorption of Eu2O3 on η‐Al2O3 and SiO2 gel
Authors: Rongchuan Liu , Yuanfu Hsia , Engelmann H. , Jing J.‐F. , Huali Jiang , Gonser U. , Krämer N. 
Published: May 2005

AbstractThe dispersity of Eu2O3 on the surfaces of Al2O3 and SiO2 gel have been studied by Mössbauer spectroscopy and x‐ray diffraction analysis. The Mössbauer data allow some insight into the structure of the dispersed Eu2O3 for both carriers. X‐ray and Mössbauer data indicate that the surface adsorption of Eu2O3 on Al2O3 is different from that on SiO2.
Identification of positive secondary ions in static sims spectra of poly(methylmethacrylate) using the deuterated polymer
Authors: Brinkhuis R. H. G. , van Ooij W. J. 
Published: May 2005

AbstractPositive static SIMS spectra of poly(methylmethacrylate) (PMMA) and perdeuterated PMMA have been compared. The usefulness of this approach for the distinction between hydrocarbon and oxygen‐containing secondary ions is demonstrated. For example, a major characteristic fragment like the one at 69 amu, which had been tentatively identified as C5H9+ by other authors, was shown to be C4H5O+.
Characterization of copper/enamel interfacial reactions during aging
Authors: Burrell Michael C. , Keane John J. 
Published: May 2005

AbstractThe interfacial reactions occurring between copper surfaces and a polyesterimide enamel coating during aging at 200°C have been investigated using XPS, AES and SEM. For coating thicknesses of 0.1 μm or greater, a copper oxide layer grows on the copper surface beneath the coating as a result of a reaction with oxygen from the atmosphere. In addition, copper becomes detectable with aging at the air/polyesterimide interface and in the bulk of the coating by surface analysis methods, indicating formation of a mobile copper species. Changes in the XPS line components indicate changes in the polyesterimide structure have occurred. Samples with very thin coatings (c. 100 Å) were also prepared and aged in an attempt to create an interface with dimensions approaching the XPS sampling depth. Upon aging, however, copper oxide grew on top of the original coating, rather than beneath it as in the case of the thicker coatings.
Transient effects during SIMS depth profiling with oxygen
Authors: Avau D. , Vandervorst W. , Maes H. E. 
Published: May 2005

AbstractBefore a steady state is reached in a SIMS experiment with oxygen primary ions, transient effects occur due to the build‐up of an oxygen profile in the sample. We studied profiles in the situation in which the variation of ionization yield, radiation enhanced diffusion, and radiation enhanced segregation are assumed to be the relevant processes. Low energy As and Sb implantations (4 keV to 10 keV) as well as homogeneously doped wafers are studied. In the transient region attention is paid to the As or Sb ion as well as to a high intensity molecular compound (AsSiO or SbSiO). Experiments are carried out using an electron beam to irradiate the sample during sputter profiling. The changes in the profile shape with varying primary energy, oxygen partial pressure and electron beam impact conditions lead to the description of a model of the enhanced redistribution due to segregation. This model includes the possibility for segregation towards the surface at the internally formed SiO2 layer.
Solid‐state diffusion and point defect studies evaluated by SIMS
Authors: Södervall U. , Lodding A. , Odelius H. 
Published: May 2005

AbstractThe applicability of secondary ion mass spectrometry to tracer diffusion study in different solids has been tested. The diffusion of B and Ge has been measured in Si single crystals under different hydrostatic pressures. The isotope effect of diffusion at different temperatures has been determined for tri‐ and tetra‐valent impurities in single‐crystal Cu and Ag.The activation volumes in Si appear non‐zero or negative, in line with an interstitial type of diffusion mechanism. The isotope effect E for Ga and Ge in Cu, and for Sn in Ag, obtained by SIMS with accuracies competitive to the best radiotracer measurements, are lower than for self‐diffusion in the noble metals, in line with simple theory based on monovacancies. Near to the melting point, E increases with temperature, which is contrary to the divacancy‐attributed tendencies reported for the isotope effect of self‐diffusion in Group 1B metals. The presently observed behaviour of polyvalent impurities at high temperatures, nevertheless, does not appear easily reconcilable with only a single vacancy diffusion mechanism.
Round Robin on combined electrochemical and AES/ESCA characterization of the passive films on FeCr and FeCrMo alloys
Authors: Marcus P. , Olefjord I. 
Published: May 2005

AbstractA Round Robin has been organized by the Working Party of the European Federation of Corrosion on Surface Science and the Mechanisms of Corrosion and Protection.1 Ten European laboratories participated in this Round Robin.2 The aim was to compare the results obtained by AES and ESCA analyses of passive films formed on FeCr and FeCrMo alloys in 0.5 M H2SO4. All participating laboratories followed a standard procedure that had been previously established by the Working Party. The recommended procedure defines the conditions for the surface preparation, the electrochemical treatment, and the surface analyses by AES and ESCA.The following aspects have been investigated.

—Polarization curves of FeCr and FeCrMo alloys exposed in 0.5 M H2SO4. Comparison of the corrosion potentials, passivation peak currents and potentials, currents in the passive region.
—Thickness of the passive films determined by AES depth profiling and by ESCA analysis.
—Composition of the films.
—Chemical states of the elements in the films, binding energies and the chemical shifts measured by ESCA.
High spatial resolution analytical electron microscopy studies on the Co/CeO2 system
Authors: Colliex C. , Ugarte D. , Wang Z. L. , Gasgnier M. , Paul‐Boncour V. 
Published: May 2005

AbstractAnaytical electron microscopy (AEM) consists of extending the information generally delivered by the electron microscope (topography, structure) with a knowledge of the chemical and electronic properties. Its major advantage is to perform higly sensitive spectroscopies, such as electron energy loss spectroscopy (EELS), on nanovolumes of materials defined and localized within their environment. It is therfore well suited to the study of complex specimens, such as catalytical products, in which there is a competion of bulk and surface properties. Metallic Co particles on supporting CeO2 layers provide an illustrative example of AEM capabilities. Atomic resolution images of surfaces and interfaces are associated with EELS spectroscopy and EELS maps to obtain a detailed view of the local arrangement of the different components, at successive steps of the chemical reaction. Nevertheless, beaminduced chemical tranformations of the system have been observed at the atomic scale. Radiation damage therefore constitutes the final limitation.
Noble gas depth profiles in amorphous TiO2 films after sputtering
Authors: Wolff M. , Schultze J. W. 
Published: May 2005

AbstractTiO2 films are formed galvanostatically in 1 N H2SO4 by anodic polarization. The resulting amorphous oxide layer is about 30 nm thick. The films are sputtered with Ne+, and Kr+ in the energy range from 2 to 9 keV. This sputter process is always combined with an implantation of the sputter ions in a partially reduced oxide. The distribution of penetration depth (1−10 nm) of implanted noble gas ions is investigated by two methods. In the top few nanometres it is derived from angle‐resolved X‐ray photoelectron spectroscopy measurements. The obtained results can be assigned approximately to a two‐layer model with an inner implantation layer (d1 = 10 nm, cAr = 10–25%) and a gas‐free surface layer (dGF = 0.5–2 nm) owing to diffusion and outgassing of the implanted noble gas ions. On the other hand, we carried out Kr+ sputter profiles of TiO2 implanted with Ar+ and Ne+ by previous sputtering. This yields an immediate decrease of the previous sputter gas (Ar, Ne) concentration which is explained by fast diffusion of Ar and Ne induced by the high temperatures during the Kr+ sputtering.
Surface segregated boron nitride on a FeSi alloy: Thermal oxidation and related segregation phenomena
Authors: Humbert P. , Essouni M. , Mosser A. 
Published: May 2005

AbstractThe surface of a Fe‐3.1 wt% Si single crystal, containing boron, nitrogen, sulphur and carbon in the ppm range, was analysed by ESCA at normal and grazing emission angle to determine both depth distribution and bonding state of the different elements. The BN‐covered surface was obtained by cacuum annealing at 850 °C. The thin BN layer remains stable on the surface during all the oxidation and heat treatments and prevents oxidation of the substrate. Oxidation only develops at the few sulphur‐covered areas, in the same way as for a totally sulphurcovered surface. The different segregation phenomena are qualitatively explained within classical segregation models.
Analysis in in situ prepared surfaces of an iron oxide based dehydrogenation catalyst
Authors: Muhler M. , Schlögl R. , Ertl G. 
Published: May 2005

AbstractAn X‐ray photoelectron spectroscopic study is presented for an industrial catalyst surface, which is in its active form only accessible after reaction under technical conditions. A high pressure‐high temperature reactor was attached to a surface analysis system. It allowed rapid transfer of a sample between the reaction environment and the UHV required for surface analysis. The active phase was identified as a ternary iron potassium oxide. No evidence was found for the previously suggested presence of a binary potassium hydroxide or carbonate phase in solid or liquid form. A new model of the active catalyst is proposed.
Characterization of supported Pd catalysts
Authors: Papp H. , Kamp P. 
Published: May 2005

AbstractSupported Pd catalysts are active for the oxidation of carbon monoxide at low temperature. To understand the catalytic action on a molecular basis, catalysts with different metal loadings have been investigated by activity tests with regard to CO2 formation, by CO chemisorption, N2 physisorption and XPS measurements. The rate of CO2 formation turns out to be independent of CO partial pressure and dependent on O2 partial pressure (0.3 order) in the pressure and temperature range investigated. The activation energy of CO oxidation has a value of 40 kJ mol−1 independent of metal loading. The specific surface are and the pore structure of the support is not significantly changed even by a metal loading as high as 17 weight per cent. The irreversibly adsorbed amount of CO—determined at 273 K in a vacuum microbalance—is linearly related to the CO2 formation rate. The dispersion determined by XPS measurements is proportional to that calculated from the CO chemisorption results.
RBS and AES depth profiles of Pd deposited on Si after annealing at different temperatures
Authors: Clement M. , Sanz J. M. , Climent A. , Martinez‐Duart J. M. 
Published: May 2005

AbstractPalladium silicide films were obtained after annealing thermally evaporated Pd layers on <111> p‐type Si substrates. The silicide layers formed at different temperatures were characterized by Rutherford backscattering (RBS) and Auger electron spectroscopy (AES). A quantification of the AES depth profiles was made by comparing the profiles with the RBS results. The sputtering time scale was converted into a depth scale using the values of the sputtering yields calculated from the RBS thickness and the AES sputter times. The transformation of the measured Auger intensities into concentration allowed a quantitative study of preferential sputtering in Pd2Si, taking into account the composition given by RBS. Finally we estimated the depth resolution of the AES profiles by comparing the width of the interfaces obtained from both techniques.
Investigation of cross‐contamination during Si‐implantion in GaAs with SIMS
Authors: Meuris M. , Vandervorst W. , Maes H. E. 
Published: May 2005

AbstractThe contamination of Si‐implantation in GaAs was analysed with SIMS. This was done by measuring the molecules composed of the ‘contamination‐atoms’ and the matrix atoms. It was concluded that there exists a co‐implantation of 14N15, 10B19F, 11B18O up to 40% of the dose for the 29Si‐implantation in the worst case and 20% of 14N2 for the 28Si‐implantation. Electrical measurements and a residual gas analysis confirmed these results. A good mass separation for the implanter was found.
Combined surface analytical and electrochemical studies for corrosion research
Authors: Strehblow H.‐H. 
Published: May 2005

AbstractThe application of several surface analytical methods in addition to electrochemical studies for corrosion research is described. Passivity of metals is taken as an example to demonstrate the advantages and limits of different in situ and ex situ methods. After a short survey of the surface analytical tools a short introduction to the passivity of metals is given. The major part of this work describes specific systems and how surface analysis provides a deeper understanding for the corrosion mechanisms and the nature of the passive layers. Fe, Cr, Fe/Cr alloys, Cu and Cu/Al alloys are discussed as examples. This review demonstrates that a combined application of a variety of methods leads to a mutual confirmation of the data and to a reliable explanation by models. For comparative results for the different studies a careful and sometimes a very difficult specimen pretreatment is a necessary requirement and may help to overcome controversial points of view.
Sulphide formation on the surface of binary AgPd alloys studied by XPS, AES, SEM/EDX
Authors: Hautaniemi J. , Heinonen M. , Juhanoja J. , Suoninen E. 
Published: May 2005

AbstractFormation of a sulphide layer on the surface of AgPd alloys has been studied by XPS, AES, SEM/EDX and optical microscopy. In accordance with earlier studies of sulphidization of AuAgCuPd alloys, no palladium‐enrichment can be observed in the sulphide layer formed on AgPd samples treated in Na2S solutions. Strong Pd‐enrichment is observed underneath the sulphide layer on the surface of the metal substrate. The enrichment takes place rather quickly and is associated with a palladium‐deficient layer underneath the substrate surface, suggesting diffusion of palladium to the surface of the metal phase.In polycrystalline materials sulphidization also takes place along the grain boundaries. The sulphide phases on the grain boundaries seem to act as channels for the migration of the silver atoms to the sample surfaces. This process leads to further sulphidization of the whole sample surface and overlaps the direct sulphidization which eventually stops because of the formation of a palladium‐enriched layer. The grain boundary connected process is strongly influenced by the composition of the electrolyte in which the sample is immersed.
Characterization by XPS and AES of oxide films formed on stainless steel 304 under various PWR conditions
Authors: Couling S. B. , Welch L. S. 
Published: May 2005

AbstractIncorporation of60Co during growth of oxide films on alloys in PWR primary coolant circuits give rise to a significant radiological hazard. These oxide films have a duplex structure consisting of a thin inner layer and an outer layer of crystallites. XPS and AES techniques have been used to examine the oxide layers produced under a variety of controlled PWR coolant conditions. The elemental ratios obtained by the various techniques can be correlated with the extent to which the surfaces are covered with crystallites. The surfaces of coupons with thick outer layers of crystals were depleted in chromium with respect to the base metal composition, while examination of a specimen from which the outer layer had been removed chemically showed a significant enrichment of chromium.The relative differences between the oxides were analysed easily by these surface techniques. However, the absolute accuracy of the elemental composition was in some doubt owing to the lack of suitable, rigorously computed sensitivity factors for use in the quantitative analysis of spectra. An attempt has been made to refine the method for producing sensitivity factors appropriate to these materials.