bluuebunny/crossref_metadata_2025_split huggingface dataset:
X‐ray photoelectron spectroscopy studies of polymer surfaces, 4—further studies of the chromic acid etching of low density polyethylene
Authors: Briggs D. , Zichy V. J. I. , Brewis D. M. , Comyn J. , Dahm R. H. , Green M. A. , Konieczko M. B. 
Published: December 2004

AbstractX‐ray photoelectron spectroscopy (XPS) has been used to study the chemical modification of low density polyethylene, high density polyethylene and polypropylene using a very mild treatment with chromic‐sulphuric acid or treatment with concentrated sulphuric acid. The treatment of low density polyethylene with CrO3‐water has been studied in detail by XPS and multiple internal reflection infrared spectroscopy. In all cases surface modification has been correlated with adhesion level to an epoxide adhesive. The XPS data are also used to discuss the adhesion of metals to CrO3‐water etched polymers and the effect of surface contaminants on adhesion to epoxides.
An alternative to the relative sensitivity factor approach to quantitative SIMS analysis
Authors: Morgan A. E. 
Published: December 2004

AbstractMeasurements have been made of positive secondary ion currents from oxygen bombardment of glass standards, obtained either from NBS or specially prepared in this laboratory. By using one fitting parameter, the ionization temperature Ti, a semi‐quantitative analysis (accurate to within a factor of 2–3) is possible on any one of these standards. This approach, whilst achieving an accuracy comparable to that obtainable using relative sensitivity factors, does not restrict the analysis to those elements for which sensitivity factors are available. Further, change of sample matrix, which can alter sensitivity factors in a seemingly puzzling fashion, can easily be rationalized and accommodated through variation in Ti. Values of Ti for 16 binary oxides lie between 5500 and 9500 K. The Ti value for a more complex matrix can be estimated on a proportional basis from these binary oxide results.
An X‐ray photoelectron spectroscopic study of gold containing a bulk antimony impurity
Authors: Proctor A. , Sherwood P. M. A. 
Published: December 2004

AbstractThe paper reports the detection by XPS of a bulk antimony impurity in a gold foil sample, as a result of its surface segregation upon heating in vacuo at 600 °C. The O 1s spectra indicate at least two possible oxygen species present in the vicinity of the gold surface. The interaction of the surface segregated antimony with oxygen does not appear to be as is reported for calcium impurities, the antimony showing the binding energy corresponding to metal. Also the amount of surface segregated antimony impurity does not seem to be as dependent as calcium impurities on previously adsorbed or gas‐phase oxygen. The use of the carbon 1s peak rather than the gold 4f peaks is found to be a more reliable calibration reference.
The use of plasmon‐loss peaks in studying the epitaxial silicon on alumina interface
Authors: Thomas J. H. , Hofmann S. 
Published: December 2004

AbstractIntense plasmon‐loss features excited by kilovolt electron beams used in AES have been used to study the Si on Al2O3 interface. Variable electron beam energies provide a means of continuously varying the electron escape depth and subsequently removing this contribution from the plasmon‐depth profiles. Parametrically varying the ion energy extrapolation of the interface width to zero ion energy yields an intrinsic interface width of 13±4 å, or about six Si atom layers.
Sputter‐depth profiling in AES: Dependence of depth resolution on electron and ion beam geometry
Authors: Duncan S. , Smith R. , Sykes D. E. , Walls J. M. 
Published: December 2004

AbstractThe precise geometrical relationship between the ion and electron beams and the sample affects the depth resolution of sputter‐depth profiles in AES. A theory is presented which predicts this instrumental depth resolution by considering the shape of the ion‐eroded crater and the corresponding orientation of the electron beam. The variation in depth resolution is analysed for a range of conditions including (a) varying ion and electron beam diameter (b) the angular orientation of the electron and ion beam and (c) the effect of misalignment of the two beams.
Preparation of brittle thermoset specimens for surface characterization by contact angles
Authors: Bystry F. A. , Penn L. S. 
Published: December 2004

AbstractA convenient and accurate method for surface analysis by contact angle studies is described. The specimen developed is particularly useful for brittle thermoset materials which must be prepared in a simple regular geometry for wetting force measurement by the Wilhelmy method. The procedure involves dip‐coating wires to make smooth cylindrical specimens of cured thermoset resin for wettability (contact angle) analysis. The results from this type specimen were cross‐checked with cast film specimen results to ensure that measured contact angles were material properties and were not influenced by geometry or presence of wire substrate. Results are presented for some modified and unmodified brittle thermoset resins showing changes in surface energetics.
Analysis of the auger electron line shape to determine the composition of CuNi alloys
Authors: Pamler W. , Röll K. 
Published: December 2004

AbstractThe quantitative analysis of alloys by Auger electron spectroscopy combined with ion beam sputtering becomes difficult when the Auger line shape depends on composition, when individual peaks overlap or when the composition is changed by preferential sputtering during ion bombardment. As an example, it is shown how these difficulties can be managed in the case of CuNi alloys. Variations of the peak shape in the alloy have been found to be a consequence of a linear superposition of the overlapping peaks of the pure elements. Therefore, the composition can be determined by a peak fitting procedure. The peak‐to‐peak amplitudes, on the other hand, are more complicated functions of the composition. It is shown how a concept including several sensitivity factors for the overlapping peaks can be used in order to determine the composition from the peak‐to‐peak amplitudes. The effects of preferential sputtering which produce an altered layer enriched in Ni can be corrected by an empirical sputtering correction factor. From these results the principal shape of the concentration profile within the altered layer has been estimated.
Simultaneous XRF and XPS analysis
Authors: Castle J. E. , Castle M. D. 
Published: December 2004

AbstractThe concept of utilising the x‐ray fluorescence spectrum, excited by bremsstrahlung radiation, whilst undertaking photoelectron spectroscopy is not new. However, it is only with modern multiprobe instruments and high quality data systems that the simultaneous display of both spectra becomes practicable. This paper explores the effective sampling depth and sensitivities across the energy range 1 to 10 keV. It concludes that the attachment of x‐ray detection equipment to an ESCA instrument is a practical and cost effective solution to the need to probe rather greater depths than XPS itself allows.
Barrier‐type anodic films on aluminium in aqueous borate solutions: 2—Film compositions by Rutherford backscattering spectroscopy and nuclear reaction methods
Authors: Skeldon P. , Shimizu K. , Thompson G. E. , Wood G. C. 
Published: December 2004

AbstractCompositions and elemental distributions of anodic films formed on aluminium in aqueous borate electrolytes have been investigated by Rutherford backscattering spectroscopy (RBS) and associated nuclear reaction methods, together with controlled crystallization of film sections in the transmission electron microscope (TEM). Films were found to consist principally of Al2O3; the outer regions of the films were contaminated with boron and, for all cases studied, the inner regions were boron‐free. In the absence of film dissolution the contaminated region represented approximately 40% of the film thickness, and this proportion did not vary significantly with changes in current density of film formation. The outer region contained about 1.5 wt% boron, probably as B2O3, and the densities of the inner and outer regions were similar to an accuracy of about 10%.
Applications of a system for real‐time imaging of analyzed areas in surface analysis
Authors: Tomich D. H. , Grazulis L. , Koenig M. F. , Grant J. T. 
Published: December 2004

AbstractA real‐time imaging system has been used to determine the analyzer acceptance area in electron spectrometers used for surface analysis. This inexpensive system uses an electron beam that is rastered across the specimen to create both specimen images and images of analyzed areas. These two images can then be superimposed on a video monitor or black and white television set for real‐time display at TV rates. The imaging system has been used to examine the properties of a double‐pass cylindrical mirror analyzer (Perkin–Elmer Model PHI‐550) and a hemispherical analyzer (KRATOS ES300). For the double‐pass CMA, the analyzed area was star‐shaped rather than the expected circular shape and in the retarding mode the analyzer pass energy had only a small effect on the size of the analyzed area; also, the minimum analyzed area did not coincide with the focal point of the analyzer as determined by an elastically back‐scattered 2 keV electron beam. For the hemispherical analyzer, the analyzed area was found to depend almost entirely on the size of the entrance slit, was slightly affected by the initial kinetic energy of the imaged electrons and the mode of operation, but was not affected by the analyzer pass energy or the size of the exit slit.
An IETS study of surface reactions applicable to adhesion
Authors: Henriksen P. N. , Gent A. N. , Ramsier R. D. , Alexander J. D. 
Published: December 2004

AbstractInelastic electron tunneling spectroscopy (IETS) has been used to study two classes of adhesion promoting compounds adsorbed on alumina: trialkoxysilanes and phosphonic acids. It has been shown that both types of compounds can condense directly with hydroxyl groups on the surface. Condensation is through the alkoxy groups in the case of the silanes and through the hydroxyl groups in the case of the acids. The silanes can further condense to form surface siloxanes. The absence of bands characteristic of the phosphoryl group in the spectra of the acids is indicative of resonance bond formation followed by ionic bonding to the surface.
New approaches to failure analysis using XPS sputter‐depth profiles
Authors: Davis G. D. , Clearfield H. M. , Moshier W. C. , Cote G. O. 
Published: December 2004

AbstractThe methodology of failure analysis and the use of XPS sputter‐depth profiles in failure analysis is illustrated in three examples: a titanium adhesive bond, a multilayer optical filter, and an ohmic contact. XPS sputter‐depth profiles supplement those obtained using AES and are essential to the failure analysis of a non‐conducting sample or one that is easily damaged by an electron beam. XPS sputter‐depth profiles also allow chemical state determination and improved quantification, especially for samples in which the Auger signals of different elements overlap.
Surface and thermal desorption investigations of chemically cleaned 316‐L stainless steel tubings
Authors: Simondet F. , di Giulio C. , Noel A. , Olliver E. , de Rugy H. 
Published: December 2004

AbstractWhen dealing with high purity gas handling, the nature of metallic surfaces in contact with the gas is a major concern because these surfaces are a possible source of gaseous pollution. Several surface treatments may be applied to stainless steel tubes used in gas handling systems, and these lead to different desorption properties. A comparison of the topographical effects accomplished by roughness and SEM measurements, and chemical effects by XPS determinations was made. Results were correlated to the outgassing behaviour of 316‐L SS surfaces, as determined by thermal desorption mass spectroscopy. It appears that similar treatments of 316‐L SS may not result in similar outgassing properties. Electropolished surfaces are smoother and present the least outgassing, although carefully cold drawn and chempolished stainless steel surfaces also show a comparable outgassing behaviour.
Investigation of surface contamination on silicon wafers with SIMS
Authors: Stingeder G. , Grundner M. , Grasserbauer M. 
Published: December 2004

AbstractCharacterization of the surface of silicon wafers is necessary for control and development of cleaning procedures. An analytical approach for investigation of surface contaminants with SIMS is proposed. The major problem is the presence of the contaminants only in the native oxide (thickness ∼1.5 nm). This means that analysis has to be performed in a surface zone smaller than the implantation depth of the primary ions. Chemical matrix effects and a changing erosion rate are encountered owing to the native oxide and the dynamic process of primary ion implantation and sputtering. Owing to the necessity of analysing extremely thin surface layers very slow sputtering has to be applied (1–10 monolayers per min.). As a consequence the secondary ion intensities are low and hydrocarbon species interfere with the elements to be analysed. For the identification of the secondary ion signals the evaluation of isotopic ratios determined with low mass resolution (M/ΔM ∼ 350) is combined with measurement of high resolution mass spectra.
Development of a numerical simulation of depth profiles of multilayers composed of very thin layers
Authors: Dapor M. , Marchetti F. 
Published: December 2004

AbstractA numerical approach is presented in order to simulate multilayer depth profiles. In many practical cases the normalized measured intensity may be described well by a superimposition of error functions. Here, calculation of the error function has been performed using an approximation formula that allows it to be obtained via a simple but accurate method.Particular attention has been paid to the development of a procedure that can be applied to the fitting of experimental data relative to depth profiling of samples composed of many very thin layers.
Combination of ion beam techniques, AES and SIMS for the analysis of samples exposed in the plasma boundary of the JET tokamak
Authors: Coad J. P. , Simpson J. C. B. , Neill G. F. 
Published: December 2004

AbstractA system combining ion beam and surface‐specific techniques for the analysis of probes exposed in the edge region of the plasma produced by the Joint European Torus (JET) is described. Among examples of the use of the system are the demonstration that 10–40% of the ionic charge flux in the boundary can be due to impurities, erosion and redeposition phenomena can be observed with small probes placed in the plasma boundary, and most of the oxygen observed on collector probes is an artefact resulting from exposure to air.
The application of ion beam bevel sectioning and post‐sputter etch treatment in Auger crater‐edge profiling
Authors: Skinner D. K. 
Published: December 2004

AbstractA method of Auger crater‐edge profiling is described that uses electronic contouring of the ion beam from a focused ion source for the sputter formation of bevelled cross‐sections. Vanishingly shallow angles can be produced by this method, allowing high lateral magnification of layered structures with in‐depth resolution equal to the best obtainable by conventional Auger profiling. The many advantages of this approach are discussed, together with details of a new approach for improving in‐depth resolution. This entails post‐treatment of the sputter‐formed bevel using low‐energy sputtering and chemically assisted reactive ion beam etching. The methods are demonstrated using samples of buried SiO2 in Si and InP/GaInAs superlattice structures.
Growth and characterization of GaAs on sapphire (0001) by molecular beam epitaxy
Authors: Diebold Alain C. , Steinhauser S. W. , Mariella R. P. , Marti Jordi , Reidinger F. , Antrim R. F. 
Published: December 2004

AbstractCrystal epilayers of (111)‐oriented GaAs have been grown successfully on sapphire (0001) substrates by molecular beam epitaxy. Although the epilayers were found to have a very high twin density, large areas (cm2) with no grain boundaries were observed. Both substrate surface preparation and temperature controlled the crystallinity. Reflection high‐energy electron diffraction (RHEED) was used to characterize the sapphire surface after ozone cleaning. RHEED patterns taken at several azimuths were consistent with an outermost layer of oxygen atoms. Powder x‐ray diffraction and rotation x‐ray photographs were used to determine growth conditions that resulted in an improvement in the crystalline order. Cross‐sectional transmission electron microscopy confirmed the crystalline nature of the GaAs epilayers. The quality of the GaAs was also characterized by photoluminescence. Finally, crystalline quality was assessed using double‐crystal x‐ray diffraction rocking curves.
The influence of chemical environment upon the mercury 5d electronic structure
Authors: Dowben P. A. , Kime Y. J. , Lagraffe D. , Onellion M. 
Published: December 2004

AbstractWe have investigated one and two monolayers of Hg adsorbed on Cu(100) by angle‐resolved photoemission. The electronic structure of one monolayer of Hg on Cu(100) is very similar to that of the free atom. Two monolayers of Hg on Cu(100) has an electronic structure that closely resembles that of bulk Hg. These results are compared to those obtained for Hg overlayers on Ag(100). We have also observed that the shallow 5d core levels of the first monolayer of Hg shift by 0.38 ± 0.05 eV to greater binding energy following the adsorption of the second monolayer of Hg.
XPS analysis of the interphase between an anaerobic adhesive and metal substrates
Authors: Hudak S. J. , Boerio F. J. , Clark P. J. , Okamoto Y. 
Published: December 2004

AbstractX‐ray photoelectron spectroscopy (XPS) has been used to study the interphase between a model anaerobic adhesive system composed of triethylene glycol dimethacrylate monomer (TRIEGMA) and a curing system consisting of cumene hydroperoxide (CHP), acetylphenyl hydrazine (APH) and saccharin (BS), and the substrates copper, iron, zinc and aluminum. Miniature cantilever beam specimens were prepared by curing beams of the adhesive against beams of the metal substrates. The specimens were then immersed in liquid nitrogen, causing the adhesive to delaminate from the substrate. XPS spectra obtained from the adhesive failure surfaces were very similar to spectra obtained from the bulk adhesive, containing peaks corresponding to carbon, oxygen and trace amounts of sulfur and nitrogen. However, the spectra also contained peaks due to trace amounts of metal or metal ions from the substrate. Spectra obtained from the substrate failure surfaces were very different from those of the corresponding adhesive failure surfaces and contained peaks due to higher concentrations of metal or metal ions and higher concentrations of nitrogen and sulfur, indicating that failure was near the interface and that both BS and APH segregated to the interface. C 1s multiplex spectra obtained from thin films of BS spin‐coated from dilute solutions onto iron, copper and zinc contained a weak component shifted from the main hydrocarbon peak to higher binding energy by ∼3.1 eV. This was more similar to the shift observed from the hydrated sodium salt of BS (Δ2.9 eV) than neat BS (δ3.7 eV), indicating that BS readily forms a complex with these substrates. When a copper foil was placed in a solution of BS and analyzed periodically in XPS, peaks due to Cu(I) were initially observed in the Cu 2p spectra, but peaks due to Cu(II) appeared after ∼110 h. The Cu(II) BS complex was also observed when a blue powder, which precipitated when a copper foil was placed in a solution of BS in methanol, was analyzed. Spectra obtained from aluminum (which does not catalyze the polymerization of the anaerobic adhesive as well as copper or iron) did not show the formation of a BS‐metal complex in any of the samples studied.
General theoretical treatment of the angular dependence of critical depths in X‐ray fluorescence spectroscopic studies of surfaces, thin films and multilayers
Authors: Scimeca T. , Andermann G. 
Published: December 2004

AbstractA general theoretical treatment is offered to obtain the critical depth (dc) values of the characteristic K, L and M x‐ray fluorescence signals as a function of sample grazing incidence angle (θi′), exit angle (θe′) and atomic number Z. It is shown, for example, that for θe′ = 1° and θi′ = 89° in going from Z = 5 to Z = 74, dc values range from 102 to 104 Å for K emission, from 30 to 500 Å for L emission, and from 10 to 50 Å for M emission provided 99% of the emerging radiation is accounted for. Detailed calculations are offered for cases when a smaller fraction of the outgoing radiation is considered. Critical depth calculations are also offered for single and multilayer thin films. The effect surface roughness has on the critical depth and the dc dependence on energy are also examined. Finally, the depth resolution is calculated for a given angular definition.
Radial distribution of heterogenized hydroformylation Rh complexes in phosphinated polystyrene beads
Authors: Terreros P. , Pastor E. , Fierro J. L. G. , Palacios J. M. 
Published: December 2004

AbstractRhodium(I) complexes anchored to 2% divinyl benzene cross‐linked phosphinated polystyrene have been prepared with chloride and pentafluorophenylthiolate ligands. The cross‐sectional distribution of the elements involved in the active complex has been examined by SEM‐EDX, and the surface composition by XPS. The combined use of both techniques revealed that Rh(I) complexes prepared from a chloride precursor form a weak bond with the phosphine groups of polystyrene, while this bond is stronger when the complex is prepared from a pentafluorophenylthiolate precursor. Owing to these chemical differences, the catalytic behaviour for hept‐1‐ene hydroformylation is quite different. While the life of a catalyst is only four reaction cycles in the former case, it is extended to more than eleven reaction cycles in the latter. In all cases, a well‐defined P (as phosphine) profile was observed, which decreased from the periphery to the centre of the beads. Such a profile was almost unaffected by the pretreatments or by the operative conditions; however, an important surface reorganization was observed just at the end of the catalyst's life. The profiles of other elements of the active component, namely Rh and Cl (or S), followed, in general, similar trends in fresh preparations but decreased markedly, especially in the ex‐chloride preparations, with the number of extraction– washing pretreatments and the number of cycles in the reaction.
Application of fast atom bombardment (FAB) for ion microscopy of a rock sample
Authors: Seyama H. , Soma M. 
Published: December 2004

AbstractA CAMECA IMS4f ion microscope was modified to accommodate a fast atom bombardment (FAB) source and used for the analysis of the thin section of a rock sample (granodiorite). In contrast to conventional SIMS using a primary ion beam, it is easy to obtain secondary ion images and mass spectra of poorly conducting material, such as geological samples, by SIMS using a FAB source where the charging effect is easily avoided with the aid of a copper grid placed on the sample surface. The difference of elemental distribution between biotite and feldspar phases in the granodiorite sample was revealed in the positive secondary ion images and mass spectra obtained by use of an O2 FAB source. The images of 23Na+ and 39K+ ions clearly showed that the separation of potassium and sodium feldspars occurred in the process of feldspar crystallization.