bluuebunny/crossref_metadata_2025_split huggingface dataset:
Auger and x‐ray photoelectron spectroscopy study of localized intergranular cracking in a nickel—chromium—molybdenum—iron alloy
Authors: Bradbury C. A. , Sturgill K. E. , McKissick D. C. 
Published: May 2005

AbstractAn unused jet engine tailpipe, fabricated from a nickel—chromium—molybdenum—iron alloy, was found to be severely embrittled after 7 years of storage. Metallurgical and mechanical tests found a larger than specification size grain structure and several very localized areas of unexplained low ductility. These were surrounded by material with normal properties. Auger electron spectroscopy (AES) studies documented the elemental composition and relative concentration at the grain boundaries. Sodium, chlorine, sulfur, iron, chromium, nickel and carbon were present. The concentration of the iron was much higher than expected, while the nickel concentration was significantly lower. The concentrations remained at these levels through 90 min of ion sputtering. X‐ray photoelectron binding energies of iron and carbon indicate that these elements were present as carbides. The presence of an abnormal chemistry at the grain boundaries, such as iron carbides, was considered to be the probable cause of the embrittlement.
Effects of morphology on the electrical and optical properties of thin bismuth films
Authors: Christensen T. M. , Dalton D. I. 
Published: May 2005

AbstractThin films of bismuth were evaporated onto polished Si(100) substrates at substrate growth temperatures which varied between 25 and 100° C. The variations in film morphology observed using the scanning electron microscope and atomic force microscope were compared to changes in the optical and electrical properties of the thin Bi films. The optical properties could be modeled using an effective medium approximation, which suggested that the roughness of the films changed with substrate growth temperature. The film roughness appeared to decrease with substrate temperature from room temperature deposition to a minimum roughness at temperatures of ∼70 °C. Higher temperatures again resulted in an increased roughness, which correlated with a change in morphology observed by SEM. The electrical resistance of the samples was not sensitive to roughness changes in the film, but did change abruptly for the higher temperature samples where the morphology was substantially different. The transverse magnetoresistance was sensitive to film structure, increasing with substrate growth temperature up to a maximum substrate temperature of 70 °C before decreasing again at higher temperatures.
Langmuir‐Blodgett films of rigid rod oligoimides on gold: An x‐ray photoelectron spectroscopy study
Authors: Atanasoska Ljiljana , Cammarata Vince , Stallman Barbara J. , Kwan Wing Sum V. , Miller Larry L. 
Published: May 2005

AbstractAngular‐resolved x‐ray photoelectron spectroscopy (ARXPS) was used to study mono‐ and multilayer films of rigid oligoimides prepared on gold‐coated glass slides by the Langmuir‐Blodgett (LB) horizontal lifting technique. The experimentally obtained total atomic ratios were in a good agreement with molecular formulae. The attenuation of the substrate Au 4f photoemissio intensities was recorded as a function of both the number of LB dips and the take‐off angles. The ratio of the thickness to the attenuation length was determined for three different oligoimides from the slopes of the linear attenuation regions. Interpretation of the thickness/attenuation length ratio was based on the models for the oligoimide LB films of oriented structures. The average tilt angle and the area/molecule used in modeling the oligoimide film structures were determined in independent experiments involving grazing angle infrared (GIR) spectroscopy, electrochemistry and LB pressure‐area isotherms. The thicknesses of the oligoimide films were calculated from the models and used to derive the value of the attenuation length from the ARXPS slopes. The attenuation length value for Au 4f core‐level photoelectrons (Ek = 1169.6 eV) was estimated to be 66–70 Å in the LB films of all three different oligoimides.
The use of metal/semiconductor structures to develop MULSAM analytical techniques
Authors: Prutton M. , Barkshire I. R. , El Gomati M. M. , Greenwood J. C. , Kenny P. G. , Roberts R. H. 
Published: May 2005

AbstractThe structures that can be fabricated by integrated circuit technology are very useful as well‐characterized samples for testing image processing methodologies in multi‐imaging instruments. Such samples are employed in the work described in this paper to evaluate schemes for correction of spectral background, substrate backscattering, surface topography and beam current fluctuation effects out of Auger images. The outstanding problems associated with the effects on Auger image contrast of sharp edges bounding overlayer structures are outlined and possible solutions are discussed.
Characterization of the annealed CoTi (110) surface and its interaction with molecular oxygen at room temperature
Authors: Rivière J. C. , Netzer F. P. , Rosina G. 
Published: May 2005

AbstractThe annealed surface of CoTi single crystal oriented (110) has been characterized by AES, low‐energy electron diffraction (LEED) and electron energy‐loss spectroscopy (ELS), and the nature of its interaction with molecular oxygen at room tempertature has been studied. In the cleanest achieveable condition (5a/o oxygen irreducible minimum), the AES and LEED observations were consistent with a model in which the outer two atom layers consisted of titanium in registry with the underlying CoTi (110). Support for the model came from ELS, in which the titanium plasmon losses were shifted upwards in energy due to the smaller unit cell volume in the titanium film, and an interface plasmon loss was also found.Reaction with oxygen up to a maximum exposure of 3000 L occurred exclusively with the titanium component, the rate of reaction being about an order of magnitude slower than that observed by other workers on pure bulk titanium. The O/Ti atomic ratios measured at all stages of oxidation by AES, and the associated fine structure at each stage in the Ti LMM Auger spectra, were consistent with a process of oxidation first to TiO and then to Ti2O3, without the higher oxides appearing simultaneously. The maximum exposure used was insufficient for complete oxidation to TiO2. The ELS observations during oxygen exposure were in agreement with the proposed process.
Determination of lubricant thickness on magnetic recording heads using XPS
Authors: Leavitt P. K. 
Published: May 2005

AbstractMany techniques are currently available for measuring lubricant thicknesses on magnetic recording disks. This paper describes a method for measuring lubricant thicknesses reproducibly and reliably on magnetic recording heads. Standard XPS disk lubricant thickness methods were used with appropriate modifications to account for substrate differences. Oxygen regions were ratioed instead of carbon, and R∞ for the heads was experimentally determined to be 0.37. Using these modifications, lubricant thicknesses were measured on heads from two different sources to try and explain file‐level operating differences.
A one‐film‐model ellipsometry program for the simultaneous calculation of protein film thickness and refractive index
Authors: Krisdhasima Viwat , McGuire Joseph , Sproull Robert 
Published: May 2005

AbstractHeterogeneous protein films are not perfectly suited to ellipsometric analysis, and commercially available software often fails to yield meaningful optical properties for such films. Here, we describe a computer program uniquely suited for calculation of the thickness and refractive index of protein films. An important feature of the new program is an algorithm that allows a search for a solution in up to four directions.
Peculiarities of the Cu LVV Auger line in copper oxide cuprates and HTSC‐materials studied by x‐ray photoelectron and Auger electron spectroscopies
Authors: Akimov A. G. , Dementjev A. P. , Le Héricy J. , Kazansky L. P. , Khodan A. N. , Langeron J. P. , Melnikova N. A. , Rakhovsky V. I. , Vignes J. L. 
Published: May 2005

AbstractAuger electron spectroscopy investigations of various copper compounds, including oxides, cuprates and high‐temperature superconducting (HTSC) YBaCuO‐type materials, show that the linewidth of the Cu LVV transition for these compounds increases with the oxygen‐to‐copper ratio. Correspondingly, for the same compounds, the intensity ratio of the satellite (Is) and main (Im) lines in the Cu 2p3/2 line measured from XPS spectra decreases. Taking into account the mechanisms of Auger electron and x‐ray photoelectron transitions, this correlation may be explained by an increase in the probability of electron transition from the O 2p to Cu 3d level in cuprates when compared with CuO. The peculiarities of Auger spectra found for YBa2Cu3O6.6–6.9 and for cuprates may be used to evaluate the quality of HTSC films by Auger microprobe.
Influence of the bombarding ion energy and surface composition on the ground‐state atom fraction in solids analysis using multiphoton resonance ionization
Authors: Pappas David L. , Hrubowchak David M. , Ervin Matthew H. , Winograd Nicholas 
Published: May 2005

AbstractMultiphoton resonance ionization (MPRI) is used to probe the desorption characteristics of ion‐bombarded surfaces of Fe, In and Ni. The effects of primary ion kinetic energy and surface chemistry on the sensitivity and accuracy of MPRI detection are examined. The relative Ni*/Ni° and In2°/In° ratios are found to increase as the energy of the incident Ar+ ion is varied from 300 eV to 1000 eV. A reflecting time‐of‐flight mass spectrometer is employed to collect efficiently the photoions as well as secondary ions, permitting accurate determination of the ground‐state atom fraction and thereby completing a detailed fundamental analysis of the analytical capabilities of the MPRI approach. The ground‐state atom fractions are found to parallel changes in surface composition and represent 30–90% of the material desorbed from ion beam‐cleaned and air‐exposed Fe and In matrices. In contrast, the corresponding secondary ion fractions vary over several orders of magnitude and are difficult to correlate with surface chemistry.
Sputtered netural and molecular ion mass spectrometries in the characterization of multilayer samples
Authors: Moro L. , Canteri R. , Anderle M. 
Published: May 2005

AbstractIn this paper we report some results obtained in the analysis of multilayer samples employed in VLSI and ULSI microelectronic technology by means of hot electron gas SNMS (sputtered neutral mass spectrometry) and MCs+ SIMS.
A direct comparison of molecular ion SIMS with a post‐ionization technique pushed to its limits is presented.
A discussion in terms of dynamic range, optimum sensitivity and depth resolution is given.
Computer‐aided resolution enhancement for XPS imaging of an uncharged single chemical species
Authors: Grabherr M. G. , Ebel M. F. , Gurker N. , Svagera R. , Mantler M. , Ebel H. 
Published: May 2005

AbstractImaging XPS can be performed by an application of the double focusing properties of the hemispherical electron energy analyser. The x‐ray photoelectron spectra originating from an area of the specimen are depicted on a multichannel plate electron detector. An increasing size of this specimen area helps to reduce the total time for the generation of an XPS image. But, together with a reduction of the time of measurement, a loss of lateral resolution has to be expected. The present paper deals with the concept of computer‐aided compensation for the loss of resolution due to an increase of the observed specimen area. The principle of this concept is based on a deconvolution of the measured x‐ray photoelectron spectra.
Relation between the intensity of Auger lines and the cross‐relaxation energy in oxygen KLL lines of oxides
Authors: Brizuela Graciela , Castellani Norberto , Puentes Mirta 
Published: May 2005

AbstractA calculation method is described and used to obtain the net ionic oxygen extra‐charge in oxides from the O KLL Auger intensities. The relation with the O KLL cross‐relaxation energies is also discussed.
First steps of the Ni–20 Cr alloy oxidation studied by Auger electron microprobe
Authors: Schmitt J. F. , Pacia N. , Pigeat P. , Weber B. 
Published: May 2005

AbstractPolycrystalline Ni‐20 Cr alloy ribbons were studied after low‐pressure oxidation (3.3 × 10−4 Pa) at 750° C by scanning Auger microanalysis with argon ion sputter profiling. Only chromium oxide is formed under our experimental conditions and a 10% mechanical predeformation (uniaxial deformation) at ambient temperature is found to promote strongly the oxide formation on the alloy surface. In effect, it notably reduces the incubation period that precedes all our oxidations. However, the presented analysis reveals that the chromium oxide distribution is very heterogenous on predeformed oxidized samples at the beginning of the reaction.
Determination of the depth profiles of ion‐implanted impurities by electron probe x‐ray microanalysis
Authors: Alexeyev Andrey P. 
Published: May 2005

AbstractThe aim of this paper is to demonstrate the suitability of electron probe x‐ray microanalysis (EPMA) for nondestructive determination of the depth profiles of ion‐implanted impurities. The intensities of the characteristic x‐ray emission of impurity atoms (P and As) were measured (on a WDX spectrometer) on the implanted specimens and references (GaP and GaAs) at three values of primary electron energy EP. The range distribution of the implanted impurity as a first approximation is given by a Gaussian distribution. A two‐parameter fitting has been developed for the determination of Gaussian parameters RP and ΔRP of the profiles, which give a minimal difference between the experimental and calculated x‐ray intensities at different EP. The dose of the implanted impurity is a third parameter that can be obtained here. The results were compared with those of depth profiles from AES (for P) and SIMS (for As) and good agreement is observed. A new method for the determination of the depth distribution of x‐ray production for the characteristic x‐rays of impurity atoms is also presented.
Influence of surface preparation on oxidation of stainless steels at high temperature
Authors: Guillamet R. , Lenglet M. , Gazin L. , Hannoyer B. , Lopitaux J. 
Published: May 2005

AbstractFourier transform infrared specular reflectance spectra at variable incidence have been recorded in order to characterize the oxide layers formed on both mechanically polished and etched surfaces of stainless steels (AISI 304 and 316). Depending on the surface preparation, the major oxides are either Cr2O3 and MnCr2O4 for polished samples or α‐Fe2O3 and Fe3O4 for etched samples in the early stages of the oxidation in air at 900°C. Secondary ion mass spectrometry depth profiles confirm the schematic structure of oxide films (developed on polished surfaces during longer exposures) deduced from infrared reflectance study.
X‐ray photoelectron spectroscopic (XPS) study of DeNOx catalysts after exposure to slag tap furnace flue gas
Authors: Rademacher I. , Borgmann D. , Hopfengärtner G. , Wedler G. , Hums E. , Spitznagel G. W. 
Published: May 2005

AbstractX‐ray photoelectron spectroscopy has been used to investigate the composition of both the surface of DeNOx catalysts (Ti:Mo:V = 92:6:2 and Ti:W:V = 85:10:5 at.%) and the material deposited from the flue gas. In spite of the charging of the surface in the spectrometer, it was possible to perform both qualitative and quantitative analysis. The deposits primarily contain Ca, Si, O, S, As, P and N. Oxidation numbers of Ca, Si, Ti, Mo, W, S and N were determined from chemical shifts in combination with line widths. There are, however, problems with the determination of the oxidation state of As owing to an influence of the exciting Al Kα radiation on the oxidation state. Nevertheless, As seems to exist both as As3+ and As5+.
Plasma processes and adhesive bonding of polytetrafluoroethylene
Authors: Kaplan S. L. , Lopata E. S. , Smith Jared 
Published: May 2005

AbstractThe virtues of chemical inertness and low surface energy which make polytetrafluoroethylene (PTFE) a valuable engineering polymer also account for the difficulty in achieving structural adhesive bonds. While plasma surface treatment has proven to be the most effective means of maximizing strength and permanence of adhesive bonds with the most inert of engineering polymers, a simple plasma treatment has proven elusive for PTFE. The following studies evaluate two very different plasma processes, activation and deposition, as a means to achieve reliable and high‐strength structural adhesive bonds. Sodium naphthalene‐etched PTFE is used as a control. Presented are ESCA data which support a theory that improvement is limited by a weakened boundary layer of the PTFE.
Interphase orientation of polyimide on polycrystalline gold, silver and Si(100)
Authors: Grunze M. , Hähner G. , Wöll Ch. , Schrepp W. 
Published: May 2005

AbstractIn this paper we present experimental data that can be used to infer the structural parameters of ultrathin polyimide films as a function of distance from the substrate surface. The polyimide films are prepared by the Langmuir‐Blodgett technique in a layer‐by‐layer fashion, and the orientation of the pyromellitimide unit in the polyimide macromolecules is determined as a function of film thick‐ness by near‐edge x‐ray absorption fine structure (NEXAFS) spectroscopy. To demonstrate that the interfacial bond determines the orientation of the polymer chains in the interphase, results for polyimide on gold, silver and Si(100) are compared.
Analysis of the polyolefin/trialkylamine primer interface
Authors: Yang D. Billy 
Published: May 2005

AbstractTertiary alkylamines of different chain lengths have been used as primers for adhesive bonding strength promotion for polyolefinic surfaces with cyanoacrylate (CA) adhesives. A combination of the construction of model polyolefin surfaces and advanced molecular‐sensitive analysis tools has been employed for understanding the promoter/polyolefin interaction at the interface. Characterization of primer structure and interfacial properties has been carried out using grazing angle reflection‐absorption Fourier transform infrared spectroscopy (GA/FTIR), ellipsometry, x‐ray photoelectron spectroscopy (XPS) and contact angle titration using different pH probe liquids. Our work has focused on the design and construction of a model polyolefin surface using a new in situ polyethylene (PE) polymerization technique to form a controllable thickness (<400 Å) of PE film on a reflective metal surface. The new technique of in situ PE polymerization is based on diazomethane chemistry. Both protonated and deuterated PE films have been successfully prepared. The results of spectroscopic investigations of these model deuterated and non‐deuterated PE surfaces are disclosed. Molecular parameters that affect adhesion promotion have been studied. The parameters studied include molecular structure and alkyl chain length of tertiary alkylamines.
The role of electron microscopy in the study of adhesion to aluminium substrates
Authors: Bishopp J. A. , Thompson G. E. 
Published: May 2005

AbstractThe analysis of the bondline in structural aluminium joints is taken as an example to illustrate how electron microscopy can be used to gain a new insight into the pheneomenon of adhesion. Scanning electron microscopy and transmission electron microscopy of ultramicrotomed sections has been used to characterize the adherend surfaces generated by the pretreatment processes prior to bonding. It is shown how a simple extension of these techniques can be used to analyse and characterize the interfacial and interphasial morphologies of the bonded joint both before and after exposure to ‘hot/wet’ environments. Results have shown that the importance of the so‐called mechanical interlocking phenomenon is related to the durability resistance of the joint rather than enhancement of the ‘dry‐state’ mechanical properties. It is also concluded that the formation of the voluminous hydrated alumina at the interface occurs post‐rupture and is not a prima facie cause. From the observed interphasial morphologies a hypothesis is advanced to explain the effect of various pretreatments on joint durability. Other analytical techniques, such as ‘parallel’ sections, AES, XPS and electron energy‐loss spectroscopy (EELS), are discussed and it is shown how these methods can be used, not only to confirm the interphasial structures but also to generate new data in their own right.A Greater understanding, therefore, of the effect of adhesive theology, environmental exposure, adherend composition and pretreatment on the interface between adhesive and adherend, can be obtained using these techniques.
Growth of anodic oxides on reactively sputtered TiNx films
Authors: Montero I. , Jiménez C. , Albella J. M. , Perrière J. 
Published: May 2005

AbstractThe anodic oxidation behaviour of reactively sputtered titanium nitride thin films deposited onto silicon substrates has been investigated in order to obtain oxynitride layers at room temperature. It has been found that small differences in the stoichiometry of the titanium nitride films may give rise to large changes in the reactivity with oxygen. Thus, a strong influence of N/Ti atomic ratio value on the oxidation kinetics is observed. Analysis of the films by Rutherford backscattering and secondary ion mass spectroscopy reveals that the oxide structure is formed by an outer oxidized thin layer composed of a mixture of TiO2 + TiNx followed by a thicker layer with oxygen atoms dissolved in the previously deposited layer of titanium nitride. After prolonged oxidation, no nitrogen is detected in the surface layer, which is only composed of TiO2. Interestingly, the thickness of the outer layer is almost independent of the formation voltage and the anodization current.
A study of the chemical composition of some cobalt silicide layer structures
Authors: Greenwood J. C. , Lamb B. , Prutton M. 
Published: May 2005

AbstractAuger and loss spectra and images have been obtained from a CoSi2 standard and a structure containing cobalt‐silicon films between a Co surface layer and a silicon substrate. The results from a Phi 590 spectrometer and the York MULSAM instrument have been compared. Quantitative analysis of the compositions of both samples has shown that elements can be used as standards along with well‐established matrix correction procedures. However, the effects of preferential sputtering in conventional depth profiling or bevel sectioning with ions lead to a complex composition distribution that is depleted in Si at the surface. The plasmon loss below the Co LVV Auger peak is enhanced in height near to the Si/silicide interface. The layer structure appears to be close to Co/Co2Si/CoSi/Si.
The application of surface imaging techniques to the study of pitting corrosion initiation in stainless steels
Authors: Baker M. A. 
Published: May 2005

AbstractA combined Auger, EDX and SEM surface imaging study of the initial stages of pitting corrosion is presented. Examples of different pitting initiation situations are shown and the importance of multi‐technique imaging to interpret the results is demonstrated. The information provided by the images is compared with theories established primarily from electrochemical results. The development of scanning probe microscopies presents the opportunity of directly studying pitting initiation using imaging. Initial atomic force microscopy images of the corrosion of sulphide inclusions in stainless steels are given and the possible capabilities of the technique for application in this field are considered.