bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discrimination between γ′‐Fe4N and ε‐Fe2–3N iron nitride compounds using PCA of Auger electron spectra
Authors: Vandendael I. , Sloof W. G. , Steenhaut O. , Hubin A. , Vereecken J. 
Published: March 2006

AbstractAES offers high spatial resolution that is useful when analysing cross sections of nitrided steels. To discriminate between different iron nitride compounds in such an analysis, so‐called factor analysis (FA) can be applied. This requires acquisition of Auger electron spectra which are associated with either the γ′‐Fe4N or the ε‐Fe2–3N phases as principal components. In this study, the N KLL and Fe LMM Auger electron spectral lines of γ′‐Fe4N and ε‐Fe2–3N phases were acquired in great detail from the pure γ′‐Fe4N and ε‐Fe2–3N phases obtained by gaseous nitriding of pure iron. To this end, two different samples of known composition were analysed. Firstly, Auger electron spectra were recorded from a nitrided layer with large γ′‐Fe4N grains (∼30 µm) on top of an iron substrate. Secondly, Auger electron spectra were recorded from an ε‐Fe2–3N outer layer (∼6 µm) with 26 at.% N, on a γ′‐Fe4N layer (∼4 µm) with 20 at.% N, created on top of an iron substrate. The latter sample was also used for FA. It is shown that principal component analysis of a series of N KLL Auger electron spectra recorded from the iron nitride double layer could be represented by three contributions. These principal components are associated with γ′‐Fe4N, ε‐Fe2–3N and the background. On the other hand, when a background subtraction was applied to the acquired N KLL Auger electron spectra, it was not possible to discriminate between the two iron nitride phases. Copyright © 2006 John Wiley & Sons, Ltd.
Characteristic analysis of electroless Ni plating layer for electronic packaging
Authors: Kim Dae‐Gon , Kim Jong‐Woong , Yoon Jeong‐Won , Lee Won‐Bae , Jung Seung‐Boo 
Published: March 2006

AbstractThe crystallization behavior of electroless Ni–P film was investigated using X‐ray diffractometry (XRD), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). XRD analyses revealed that the amorphous state of the as‐plated Ni–P film was crystallized by heat treatment at 573 K for 1 h. Two peaks were observed simultaneously, indicating Ni and Ni3P compounds. Convergent beam electron diffraction (CBED) pattern analyses confirmed a size of the Ni3P in the crystallized Ni–P layer of 50–70 nm. The contact resistance decreased with a heat treatment, which is mainly due to the crystallized Ni–P layer and the grain growth. The activation energy calculated from DSC analyses using the Kissinger equation was 195.2 kJ/mol. Copyright © 2006 John Wiley & Sons, Ltd.
Interfacial reaction during MOCVD growth revealed by in situ ARXPS
Authors: Brevet A. , Chassagnon R. , Imhoff L. , Marco de Lucas M. C. , Domenichini B. , Bourgeois S. 
Published: March 2006

AbstractAngle‐resolved X‐ray photoelectron spectroscopy (ARXPS) experiments were performed to study in situ the reaction at the film–substrate interface during metal organic chemical vapor deposition (MOCVD) growth of TiO2 thin films deposited on the silicon substrate. The in‐depth distribution of chemical species was determined using several ARXPS thickness calculation models considering either single or bilayer systems. By the comparison of two single‐layer models, the presence of a second layer composed of silicon oxide was evidenced. High‐resolution transmission electron microscopy (HRTEM) observations confirmed the stratification of the film in two layers, as well as the perfect wetting of the surface by TiO2, irrespective of the model used. The contribution of the ARXPS bilayer model was demonstrated by the agreement of the values of film thickness obtained by both techniques. Nevertheless, the correlation between each layer's thickness was only possible by taking into account chemical species mixing. Indeed, the presence of oxidised silicon in the upper TiO2 layer, in addition to that of the SiOx interlayer, has to be considered to interpret ARXPS results in a correct way. Copyright © 2006 John Wiley & Sons, Ltd.
Computer program for the grain analysis of AFM images of nanoparticles placed on a rough surface
Authors: Chuklanov A. P. , Ziganshina S. A. , Bukharaev A. A. 
Published: March 2006

AbstractSize is one of the most important characteristics of nanostructures and determines their properties. That is why it is very important to control the size and shape of these structures. Atomic force microscopy (AFM) is widely used to visualize 3‐D nanostructures, for example, nanoparticles placed on a surface. However, in many cases it is rather difficult to obtain accurate information about the size distribution of nanoparticles because of the complex structure of the substrate surface on which the particles are placed. Existing programs for grain detection and size distribution of nanoparticles are often not able to correctly process such AFM images of a surface. In this work, we propose to combine the existing methods for the grain detection and a priori information about shapes of nanoparticles. In particular, this allowed us to obtain better results in the grain analysis of sensors, which consisted of palladium nanoparticles grown on different substrates. Copyright © 2006 John Wiley & Sons, Ltd.
Fibronectin adsorption on Fe–Cr alloy studied by XPS
Authors: Galtayries A. , Warocquier‐Clérout R. , Nagel M.‐D. , Marcus P. 
Published: March 2006

AbstractImproved knowledge of the chemical composition of biomaterial surfaces and a better understanding of interactions between biomolecules and material surfaces will allow a more rational design of biomaterials. Surface characterisation of alloys before and after their interaction with proteins is an essential aspect of this approach. In this work, the interactions of fibronectin with stainless steel surfaces (Fe–17Cr alloy) were studied by X‐ray photoelectron spectroscopy (XPS). Different solution concentrations of fibronectin were tested (0, 8, 60, 120 and 240 µg ml−1) in interaction with the stainless steel sample. N 1s, C 1s, Cr 2p and Fe 2p core level spectra were systematically recorded and compared. The results indicate that fibronectin is adsorbed on the stainless steel surface. The alloy surface composition and oxide thickness are almost unchanged (Fe2O3—Cr2O3 + Cr(OH)3) in presence of the protein, whatever the protein solution concentration. The isotherm of fibronectin adsorption at 37 °C was measured. A saturation is clearly reached for solution concentrations greater than 60 µg ml−1. On the plateau, the equivalent protein thickness is 6.3 nm, corresponding to one fibronectin monolayer. Copyright © 2006 John Wiley & Sons, Ltd.
Auger analysis and simulation of electronic states for Ge33As12Se55p‐Si heterojunction
Authors: Shchurova T. N. , Savchenko N. D. , Kondrat A. B. , Opachko I. I. 
Published: March 2006

AbstractWe present experimental data on Auger analysis of the amorphous Ge33As12Se55 filmp‐Si crystal heterojunction. The investigated depth profiles of the chemical components at the interface for the heterojunction revealed the presence of GeO2 and As2O3 from the film side and SiO2 from the crystal side in the interfacial region. The energy level diagram of the heterojunction was constructed on the basis of linear combination of atomic orbitals method and pseudopotential. Comparison of the results of simulation with experimental data shows applicability of the suggested theoretical approach to the computation of the energy band diagram of amorphous–crystalline heterojunctions taking into account the presence of electronic states at the interface. Copyright © 2006 John Wiley & Sons, Ltd.
Tip shape reconstruction of the probes for shear‐force and near‐field microscopes
Authors: Chuklanov A. P. , Bukharaev A. A. 
Published: March 2006

AbstractThis work is devoted to reconstructing the tip apex of the probes for shear‐force and scanning near‐field optical microscopes. The lateral resolution of these microscopes strongly depends on the tip radius of the corresponding probes. The transmission electron microscope (TEM) is used for estimating the tip radius as a rule. However, it is rather difficult to use TEM in the routine experiments. We present the method for determination of the tip shape using the special test samples. Two types of tips have been used: the homemade electrochemically etched W microwires and the commercial fiber probes. The estimation of the tip radius was made from the tip apex, which was extracted by our deconvolution method from the corresponding experimental images obtained on a shear‐force microscope. Additional TEM experiments allowed us to compare the results obtained by these two independent methods. Correlation was investigated between the scanning near‐field optical microscopy (SNOM) lateral resolution and the reconstructed tip apex of the fiber probe used in the corresponding experiment. Copyright © 2006 John Wiley & Sons, Ltd.
Study of X‐ray absorption near‐edge structure with a photoemission electron microscope
Authors: Zhang Zengming , Ding Zejun , Yoshikawa Hideki , Shimizu Ryuichi 
Published: March 2006

AbstractThe contribution to total electron yield (TEY) from all emitted electrons consisting of photoelectrons, Auger electrons, their inelastic‐scattering background and secondary electrons that are excited by X rays with energies near the Ag L3 edge was calculated by a Monte Carlo simulation method that describes electron scattering processes in solids as well as the secondary electron cascade production. The simulated TEYs at different energies are very close to the experimental values, and the ratio of TEYs at the X‐ray energies of 3370 and 3340 eV also agrees with the measured one. The secondary electrons contribute ∼65% to all emitted electrons; while ∼30% is due to the widely distributed energy‐loss background for inelastic scattered electrons. X‐ray absorption near‐edge structure (XANES) spectrum in TEYs simulated on the basis of a Monte Carlo method reproduces the measured spectrum with considerable success. Copyright © 2006 John Wiley & Sons, Ltd.
Angle‐resolved XPS study of thin oxides after wet cleaning on Si0.8 Ge0.2 substrates
Authors: Martinez E. , Abbadie A. , Renault O. , Cayrefourcq I. , Quiais‐Marthon S. 
Published: March 2006

AbstractOne challenge in the downscaling of complementary metal‐oxide semiconductors (CMOSs) is surface cleaning without the use of strong chemical and mechanical forces, which might damage the patterns.1, 2 We present in this paper the chemical surface properties of wafers after different types of wet cleaning of single wafers, using notably the advanced additive technologies: HF‐O3‐based or SC1‐like‐based cleaning. Angle‐resolved X‐ray photoelectron spectroscopy was used to analyse the chemical oxide composition and thickness, as well as the interface structure. On both Si and Si0.8Ge0.2 substrates, less contamination and a better oxide quality were obtained with the addition of H2O2 in SC1‐like solutions. On Si0.8Ge0.2 substrates, the oxide was mainly composed of silicon oxide. Germanium was located at the interfacial layer. Copyright © 2006 John Wiley & Sons, Ltd.
Combined AES and TOF‐SIMS analysis of a thermally treated Ag/Ti/Al metallization system
Authors: Scheithauer U. , Treichler R. 
Published: March 2006

AbstractBoth Auger electron spectroscopy (AES) and time‐of‐flight secondary ion mass spectroscopy (TOF‐SIMS) were applied to study a three‐layer backside metallization stack that was thermally treated up to temperatures above the normal process temperature. In addition to conventional sputter depth profiling, we applied a more sophisticated sample preparation method—in situ low angle cross sectioning. This way the depth scale was enlarged approximately by a factor of 20, and therefore transferred to lateral dimensions. This allows a more detailed AES analysis of the metallization system using mappings of elemental distributions. The TOF‐SIMS depth profiles were recorded as a function of the lateral geometric coordinates and in depth as a function of the sputter ion dose. This way it was possible to analyse the three‐dimensional sample composition. Copyright © 2006 John Wiley & Sons, Ltd.
Oxidation of PbSnTe solid solutions and of PbSn alloys
Authors: Berchenko N. N. , Nikiforov A. Yu. , Fadeyev S. V. 
Published: March 2006

AbstractComposition of oxide and oxide–semiconductor interface in binary chalcogenide solid solutions of PbTeSnTe and PbSn alloys was analyzed by method of equilibrium condensed phase diagrams and experimentally studied by X‐ray diffractometry (XRD), Raman spectroscopy, and Auger electron spectroscopy (AES). In accordance with the PbSnTeO equilibrium phase diagram, thermal oxidation of both PbSnTe and PbSn compounds proceeds with the initial preferential oxidation of tin to SnO2. Tin oxide dominates the composition of the growing oxide layer and prevents PbTe and Pb from oxidizing to PbTeO3 and PbO, respectively. Formation of SnO2 is followed by tellurium precipitation at the oxide–semiconductor interface. Two other oxide phases, PbSnO3 and Pb2SnO4, predicted by both PbSnTeO and PbSnO equilibrium phase diagrams were observed only in the thermally annealed PbSnTe solid solution. Copyright © 2006 John Wiley & Sons, Ltd.
Microstructure of kaolin spheres produced by a gel‐casting process with a biopolymer additive
Authors: Chumnanklang Rung‐Arun , Jaroenworaluck Angkhana , Panyathanmaporn Thammarat , Supothina Sitthisuntorn 
Published: March 2006

AbstractOver the past few years due to increased environmental awareness, there has been great interest in improving ceramic processing to reduce the use of organic solvent and synthetic binders. This work is focused on a gel‐casting process using a biopolymer that is environmentally friendly, easy to burn out and inexpensive. Starch was employed as a binder and kaolin clay was used as the starting material. To fabricate kaolin spheres, aqueous kaolin slurry was mixed with a starch solution. A small volume of the kaolin‐starch solution was added to a vegetable oil at high temperature. The starch then formed a strong, cross‐linked gel and immobilized the clay powders into the desired spherical shape. The kaolin spheres were then dried and sintered at different temperatures for 1 h. The phases present in the spheres was identified by X‐ray diffraction (XRD) analysis. The microstructure and dimensions of the kaolin spheres were examined using a field emission scanning electron microscope (FE‐SEM) in conjunction with energy dispersive spectrometry (EDS). An image analysis technique was used to identify the pore volume of the spheres. Copyright © 2006 John Wiley & Sons, Ltd.
Effective energy loss function of silver derived from reflection electron energy loss spectra
Authors: Zhang Z. M. , Ding Z. J. , Li H. M. , Tőkési K. , Varga D. , Tóth J. 
Published: March 2006

AbstractThe electron inelastic scattering in silver is studied both experimentally and theoretically. The reflection electron energy loss spectroscopy (REELS) spectra were measured using the ESA‐31. It is shown that the surface excitation is enhanced with decreasing primary energy. For the higher resolution spectra with the narrower energy distribution of elastically scattered electrons, the Tougaard's recursive formula describes inelastic scattering cross section from the measured energy loss spectrum as well as the extended Landau approach. At low primary energies, the differential inverse inelastic mean free path (DIIMFP) for low loss energies extracted by Tougaard's recursive method is smaller than that by the extended Landau approach. The latter method is better for measured REELS spectra with a large full width at half maximum (FWHM) of elastic peak (e.g. for a CMA). The effective energy loss function (EELF) has been derived from these experiments based on the extended Landau approach. The Monte Carlo simulated REELS spectra with the derived EELF agree well with the experimental spectra. Copyright © 2006 John Wiley & Sons, Ltd.
Probing the electronic structure of NiX, (X = B, S, P) catalysts with XPS
Authors: Diplas S. , Jørgensen S. , Taftø J. , Tønnessen T. , Knutsen T. , Lehrmann J. , Våland T. , Abel M.‐L. , Watts J. F. 
Published: March 2006

AbstractAmorphous films of NiB, NiP and NiS were produced by electrodeposition on pure polycrystalline Ni. The films were studied with X‐ray photoelectron spectroscopy (XPS). Changes in the Auger parameter (AP), peak energy shifts and changes in the Ni 2p shake up satellite intensity and energy were used to probe the electronic changes occurring upon alloying Ni with P, S and B. It is suggested that the Ni sites experience a higher electron density in the alloys than in the pure element and this could be the reason for the increased catalytic activity. Copyright © 2006 John Wiley & Sons, Ltd.
Intrinsic and extrinsic contributions to plasmon excitations in electron emission processes
Authors: Gervasoni J. L. , Kövér L. 
Published: March 2006

AbstractIn this work, we study in detail the process of excitation of bulk and surface plasmons during the emission of electrons in the proximity of a solid surface. We take into account the effects due to electron transport (extrinsic contributions) and residual hole (intrinsic contributions).We use the dielectric response theory and the specular reflection model. The results obtained for Al metal illustrate that, depending on the distance from the surface, the separation of extrinsic and intrinsic contributions could be ambiguous because of interference effects between the photoelectron and the photohole present in both processes. Copyright © 2006 John Wiley & Sons, Ltd.
Finite Integer Computations: An Algebraic Foundation for Their Correctness
Authors: Glesner Sabine 
Published: March 2006

Abstract
Even though computations on finite integer representations are as old as computers themselves, there is one problem that has been inexcusably neglected: integer computations in programming languages do not operate on the ring [inline-graphic not available: see fulltext] of integer numbers but only on finite subsets of it. Changing the size of integer representations may change the results of operations performed on them in unexpected ways. In particular, increasing the representation size of intermediate results during computation may lead to incorrect final results. In this paper, we develop an algebraic foundation for integer arithmetic under changing representation sizes and, in particular, a criterion for safely replacing one finite integer arithmetic by another. This safety criterion has also been verified in the theorem prover Isabelle/HOL. Based on this formal development, we not only reveal and explain an inconsistency in the Java Card integer arithmetic but also propose an optimization for Java Card integer expressions and their safe transformation into Java Card bytecode. We also discuss the application of this safety criterion to constant folding, a standard compiler optimization, for Java and C compilers.
An exploratory retrospective study of people suffering from hypersensitivity illnesses who attend medical or classical homeopathic treatment
Authors: Kimby C.K. , Henningsen Inge , Fønnebø Vinjar , Launsø L. 
Published: March 2006

AbstractThe objective of this study is to describe patients who had treatment for hypersensitivity illnesses by general practitioners (GPs) or classical homeopaths (CHs) and the patients’ self-reported effectiveness of the treatment received. The data stems from an exploratory retrospective study amongst 88 Danish patients (response rate 58%) suffering from hypersensitivity illnesses, who chose treatment from one of six GPs or one of 10 CHs who participated in the project. The patients themselves selected their treatment. The GPs or the CHs considered that the patient's treatment was complete or that the patient was in a situation of current ‘maintenance treatment’. The patients’ primary reason for consulting the GP or the CH was that they were suffering from hypersensitivity illnesses.No significant difference was found between the two groups of patients in relation to age, education and duration of hypersensitivity symptoms. The CH patients were more likely to be employed in teaching, research, health care or the social sector compared to GP patients. The two groups of patients were similar in respect of their health at the start of the treatment, 57% of the patients who consulted a CH experienced an improvement of their state of health compared to 24% of the GP patients. Both groups of patients experienced an improvement of their psychological health after treatment. Logistic regression analysis showed that the GP or CH was the only significant effect variable. The results are based on the patients’ retrospective, self-reported effectiveness of the treatments.
Quadrupole correlations governing the pattern of jet noise
Authors: Ribner H. S. 
Published: March 2006

The effects of convection and refraction dominate the heart-shaped pattern of jet noise. These can be corrected out to yield the small ‘basic directivity’ of the eddy noise generators. The observed quasi-ellipsoidal pattern was predicted by Ribner (1963, 1964) in a variant of the Lighthill theory postulating isotropic turbulence superposed on a mean shear flow. This had the feature of dealing with the joint effects of the quadrupoles without displaying them individually. The present paper reformulates the theory so as to calculate the relative contributions of the different quadrupole self and cross-correlations to the sound emitted in a given direction. Some minor errors are corrected.Of the thirty-six possible quadrupole correlations only nine yield distinct non-vanishing contributions to the axisymmetric noise pattern of a round jet. The correlations contribute either cos4θ, cos2θ sin2θ or sin4θ directional patterns, where θ is the angle with the jet axis. A separation into parts called ‘self noise’ (from turbulence alone) and ‘shear noise’ (jointly from turbulence and mean flow) may be made.The nine self-noise patterns combine as
$A\; cos^4\theta(1)+A\; cos^2sin^2\theta(\frac{7}{8}+\frac{7}{8}+\frac{1}{8}+\frac{1}{8})+A sin^2 \theta (\frac {12}{32} &amp; + &amp; \frac{12}{32}+\frac{7}{32}+\frac{1}{32})\\
&amp; = &amp; A(cos^2\theta+sin^\theta)^2 = A;$
this is uniform in all directions as it must be, arising from isotropic turbulence. The two non-vanishing shear-noise correlation patterns combine as
$B\;cos^4\theta (1) + B\;cos^2\theta sin^2\theta(\frac{1}{2})=B(cos^2\theta+sin^2\theta)^2 = A;$The overall ‘basic’ pattern (self noise plus shear noise) thus has the form A + B(cos2θ + cos4θ)/2; this is a slight change from the previous result. The dimensional constants A and B are of comparable magnitude; the pattern in any plane through the jet axis thus resembles an ellipse of modest eccentricity.Frequency spectra are also discussed, following the earlier work. Since the self noise depends quadratically on turbulent velocity components and the shear noise only linearly, there is a relative shift of the self noise to higher frequencies. This in conjunction with refraction figures in the explanation of the deeper pitch of jet noise radiated at small angles to the axis.Finally, the predictions are shown to be compatible with recent experimental results.