bluuebunny/crossref_metadata_2025_split huggingface dataset:
Precision In X-Ray Data Computed By Monte Carlo Calculations
Authors: Lifshin Eric , Linsebigler Amy , Gauvin Raynald 
Published: July 2020

Abstract
The analytical expressions used in ZAF and ϕ(ρz) calculations give single values for the composition of each element for a single set of intensity measurements from samples and standards. Confidence intervals in composition are established by looking at the variability of repeated measurements. They are usually attributed to x-ray counting statistics or experimental reproducibility factors such as sample repositioning. Uncertainty in the equations themselves or the parameters that go into them are rarely considered. The derivations of ZAF and ϕ(ρz) equations are primarily based on the case where flat single-phase regions, relative to the x-ray excitation volume, are examined using normal electron beam incidence. Use of these equations has been extended to non-normal electron beam incidence as well as the quantitative analysis of layered structures, but usually with less theoretical justification. Finally, special experimental cases including porous structures, rough surfaces, vertical interfaces and small particles are very difficult or impossible to model by the single application of a set of analytical equations to convert measured x-ray intensities to elemental composition.
Compound Standards For Light Element Eds In Aem, Sem And Lvsem
Authors: Boyes E D 
Published: July 2020

Abstract
For a number of years we have used in our laboratory a simple extension to light elements of the classical ClifF-Lorimer approach using stoichiometric compound standards containing pairs of heavier elements to determine independently the EDS detector sensitivity contribution to quantitative analysis in the AEM. It is now also extended to direct light element LVEDS analysis in the SEM at low voltage (&lt;5kV). This approach may be more practical, accessible and easily reproducible for routine use than the elegant custom thin film fabrications reported by Egerton, but the latter method has other substantial advantages, including well defined thicknesses, in the most sophisticated applications. As the types of advanced materials have expanded to include ceramics and polymers the requirements for analysis have also changed. In many cases the light elements are now the majority species in advanced materials and the corrections based on older standards are huge; and therefore inevitably rather limited in accuracy.
The Origin Of Electrical Activity At Grain Boundaries In Perovskites
Authors: Kim Miyoung , Browning N D , Pennycook S J , Sohlberg K , Pantelides S T 
Published: July 2020

Abstract
The electrical activity of grain boundaries in perovskites, of which SrTiO3 is a model system, is the basis for their use as capacitors, varistors and positive-temperature coefficient resistors. In related materials this same electrical activity is often detrimental. The outstanding example of a negative effect is the reduction in critical current by several orders of magnitude across grain boundaries in YBa2CU3O7-δ as the boundary misorientation is increased from 0°-45°. Grain boundaries are also likely to profoundly affect properties such as domain wall motion in ferroelectric and magnetic perovskites. The origin of the electrical activity is ubiquitously attributed to the existence of grain boundary donors, usually assumed to be impurities, which set up a double Schottky barrier as they are screened by dopants in the adjacent bulk crystal. We show here, that although electrical barriers can doubtless be modified by dopants, the grain boundary structure itself is the intrinsic origin of the socalled grain boundary donors.
Segregation In Cocrptta/Cr Magnetic Recording Media Measured By Eftem
Authors: Bentley J , Wittig JE , Nolan TP 
Published: July 2020

Abstract
Development of high-density longitudinal magnetic recording media (used for computer hard disks) with good noise performance and high thermal stability requires optimization of both alloy composition and processing methods. In CoCr(PtTa) thin films, intergranular Cr segregation is responsible for decoupling the magnetic exchange between the small ferromagnetic grains. The corresponding Cr depletion within the grains affects the “bulk” magnetic anisotropy. However, the nanoscale structural and chemical details that are needed for modeling and for guiding material development are not well understood. Energy-filtered transmission electron microscopy (EFTEM) has been used to characterize a series of CoCrTa/Cr, CoCrPt/Cr, and CoCrPtTa/Cr media sputtered under various processing conditions, in order to understand their structure-property-processing relationships.
Processing typical for hard-disk media was used: 30 or 60-nm films of a Cr underlayer followed by a Co alloy were d.c. magnetron sputtered onto a NiP-plated Al substrate pre-heated to 250°C.
Exelfs As A Tool For Investigating The Local Structure Of Bulk Glass-Forming Metal Alloys
Authors: Alamgir F, M , Ito Y , Williams D B , Jain H 
Published: July 2020

Abstract
The discovery of amorphous, or glassy, metallic alloys in 1959 posed an intellectual challenge. How can one describe the structure of glasses when there is no long-range periodicity? What can the structure tell us about why certain metal alloys form glasses more easily than others? First, some universal characteristics, if any exist, of the structure metallic glasses needed to be found. A convincing model was proposed for the structure of metallic glasses based on Bernal’s dense random packing (DRP) structure. Central to this proposal is the idea that the structure of metallic glasses is that of the random filling of space by non-interacting identical spheres. In this model, strongly directional interatomic bonds do not play an important role in determining the structure of metallic glasses. This model is hpwever in conflict with one proposed by Chen, which correlates increased glass formability with increased chemical interaction between dissimilar atoms.
Atom Probe Field Ion Microscopy Of Multilayer Thin Films
Authors: Larson D J , Petford-Long A K , Cerezo A , Anthony T C , Miller M K 
Published: July 2020

Abstract
Multilayer film (MLF) structures which exhibit giant-magnetoresistance (GMR) properties have applications in the areas of magnetic recording and computer memory. The magnetic properties of MLF structures are dependent upon structural and compositional variations at the atomic level. Thus, structural characterization with high spatial resolution, especially at layer interfaces, is important in order to optimize device performance with respect to processing and operating conditions. Atom probe field ion microscopy (APFIM) is one technique that has the capability to characterize the local structure and composition of MLF devices with sufficiently high resolution. However, a major difficulty has been successful specimen preparation from MLF materials, which requires fabrication of a sharply pointed needle (radius &lt;50 nm) containing the layers of interest in the apex region. Research on specialized field ion specimen preparation techniques which use focused ion beam milling has recently enabled nanoscale MLF structures to be investigated. In the present paper, the application of atom probe microanalysis to two different MLF structures is presented.
Complex Layer Stacking In Muscovite: A Hrtem Study
Authors: Ma Chi , Rossman George R 
Published: July 2020

Abstract
One-, two- and three-layer polytypes are common in muscovite (sheet silicate). Based on high-resolution transmission electron microscopy (HRTEM) and analytical electron microscopy (AEM) examinations, we report in the discovery of complex 5-layer and 7- layer polytypes in natural muscovite for the first time (Fig. 1) and the implications of polytype transitions.
Three main structures are found in muscovite crystals in a sample from Oreana, Nevada, which are 1M, 2M1, and a disordered structure often containing short-range ordered stacking sequences. On the scale of a few micrometers, muscovite occurs as ordered crystals, disordered crystals, and crystals with regions of ordered and disordered layer stacking.
Short-range ordered 5- or 7-layer repeats are found in some disordered structures where single 4-, 6-, 9- or 10-layer intergrowths occur occasionally with 2- and 3-layer repeats. Such complex polytypes have not been observed before in either natural or synthetic muscovite, although 5- and 7-layer structures are commonly present in trioctahedral micas (i.e., biotite) (Baronnet, 1992).
Boundary Analysis Of SrTio3 Ceramic Condenser
Authors: Kawasaki Masahiro , Yoshioka Tadanori , Sato Shigeki , Watanabe Kazuto , Shiojiri Makoto 
Published: July 2020

Abstract
SrTiO3-based semiconducting ceramics are widely used to electric devices such as dielectric condensers and varistors due to their properties of high dielectric constant, high dispersion frequency and small temperature dependence of the dielectric constant. The electric properties of these ceramic devices have been studied and found to be deeply influenced by the crystal growth mechanism, the grain boundary layer characteristics and the sintering atmosphere that is represented by such factors as oxygen partial pressure and processing temperature which relate to the atom vacancy formation. Atom vacancies, which play an important role to the electrical properties, have been detected by cathodoluminescence (CL) spectroscopy with scanning electron microscopy (SEM).
A ceramic condenser (Sr0.94Ca0.05Ba0.01)0.99TiO3 was investigated by Hitomi el at: using transmission electron microscopy (TEM). The material is a boundary layer (BL) semiconducting ceramic condenser, having dielectric layers between semiconducting grains. The same condenser material was investigated in this report at the grain boundary region using high resolution (scanning) transmission electron microscope (TEMSTEM) capable of High Angle Annular Dark Field (HAADF) technique.
Microstructural Characterization Of The Pd-Ge Ohmic Contact On Gaas By Cross-Sectional Transmission Electron Microscopy (Tem)
Authors: Radulescu F , McCarthy JM 
Published: July 2020

Abstract
In the last decade, Pd-Ge contact system emerged as the most promising replacement of the Au-Ni-Ge alloy, still used by most of today's GaAs technology. Its better electrical properties stem from the fact that contact formation is based on a series of solid state reactions without any melting of the metal thin films and the GaAs substrate taking place during annealing. Research studies by E.D. Marshall et al. (1) demonstrated that thermally stable contacts with low resistivities could be achieved by low temperature annealing of Pd and Ge thin films. Their studies also revealed that the excess Ge is regrown on top of the GaAs substrate by a solid state epitaxy mechanism.
Typical TEM cross-sectional specimen preparation techniques limit the electron transparent area and make the global characterization of the contact difficult. In this study, we employed a focus ion beam (FEB) method as described by Bassile et al.(2), which allowed us to observe a minimum of 4 microns of the interface cross section in each of the specimens examined.
Measurement Of Interfacial Segregation In Aluminum-Magnesium Alloys Using A Feg-Tem And Eds
Authors: Vetrano JS , Henager CH 
Published: July 2020

Abstract
Aluminum-magnesium alloys are currently being utilized in lightweight automotive components and their good strength and weldability characteristics has made them candidates for increased use. The primary problem with using aluminum alloys for automotive applications is their relatively low formability. Superplastic forming (SPF) is a viable method for producing high elongations and is enabled in these alloys by the manipulation of intermetallic particles (e.g. Al3Sc) that restrict grain growth at the high homologous temperatures necessary for this technique [1]. SPF of Al-Mg-Mn-Sc alloy has yielded elongations of over 600% [2]. However, Al3Sc particles age rapidly at high temperatures which can reduce their strengthening characteristics following deformation. It has been experimentally observed that the addition of Zr to Al-Sc alloys retards the aging of the Al3Sc precipitates [3]. This is beneficial for high temperature conditions like superplastic forming and welding. In this study we examine the location of Zr in the strupturc and how it may be inhibiting particle aging.
A Tem Investigation Of Nanoparticle Contact
Authors: Yao Y , Thölén AR 
Published: July 2020

Abstract
A comprehensive understanding of the relation between structure and properties in nano-materials calls for an extensive knowledge of the adhesion between nanoparticles. Electron diffraction contrast from the stress field caused by adhesion between contacting particles yields a detailed information on surface energy, grain boundary energy, dislocation and interphase formation mechanisms. However, the image interpretation is hindered by the scarcity of defined image condition data to fit the theoretical simulations due to the non-trivial TEM experimental situation on such a nanometric scale.
In our contribution, we challenge the above characterization complications by initiating CBED, HREM, and EELS on contacting nanoparticles with a CM200 FEG TEM. The main objective of our investigation is a quantitative simulation of the contacting stress field images from contacting nanoparticles and a quantitative characterization of the adhesion properties. In our approach, we started with cobalt particles which were coherently precipitated in a Cu-Co0.2wt% alloy, and then extracted using the carbon evaporation replica technique.
Interfacial And Surface Study Of Mo-Au And Al-Ag Bilayers For Si-Based Photodetectors
Authors: Li Mary J , Aslam S , Chen TC , Finkbeiner FM , He C , Kelley RL , Mott DB , Stahle CK , Stahle CM , Wang L 
Published: July 2020

Abstract
Bilayer thin films have been utilized in superconducting transition-edge sensors (TES) for photodetector development. A TES is formed with a normal metal conductor film and a superconductor film, so called bilayer, deposited on a subtract. In its,transition temperature region, the resistance of the superconductor film is extremely sensitive to the temperature. When an incident radiation ray arrives, the temperature of the bilayer increases, leading the resistance increases tremendously. A superconducting quantum interference device measures the current variation for read-out. By varying the relative thickness of the normal metal conductor layer and the superconductor layer, one can adjust the transition temperature of the bilayer to a desired range according to the proximity effect. TES bilayers are fabricated on Si-based substrates for the development of infrared, ultra-violet, and x-ray detectors.
Various normal and superconducting metal combinations are considered as bilayer candidates. When two metals are brought together, the concerns usually rise to those materials issues that may affect TES performance.
Al Compositional Profile In Algaas/Gaas Quantum Wells
Authors: Cai D Q , Zou J , Cockayne. D J H 
Published: July 2020

Abstract
The TEM thickness fringe method [1] was developed as a potential routine technique to determine compositional profiles in quantum well systems. This technique has the advantages that a) TEM sample preparation is simple and the experiment is easy to set up and b) thickness fringe profiles show fine structure which is sensitive to chemistry [2]. In this paper, we demonstrate the ability of the method to measure the chemical abruptness at the interface between two layers of different composition.
90° wedge AlGaAs/GaAs TEM samples were prepared by the cleavage method, where the samples were cleaved along two orthogonal {110} planes. The samples were mounted on Cu grids and were investigated in a Philips EM430 TEM. Samples were orientated to the [100] direction precisely and bright-field images were acquired digitally using a CCD camera. Fig 1 shows an enlarged image of thickness fringes.
Since the edges of samples are 90° wedges, the thickness at any point can be accurately determined and the fringe profile can be compared with fringe profiles calculated for a range of Al compositions.
Thermal Stability of The Copper/Tantalum Interfaces In Advanced Microelectronic Metallization
Authors: Kwon Kee-Won , Lee Hoo-Jeong , Sinclair Robert 
Published: July 2020

Abstract
In the copper metallization adopted for better speed and reliability in microelectronic devices, the choice of underlayer is one of the major concerns. Its requirements include low electrical resistance, adhesion to Cu and adjacent dielectric materials, confinement of Cu from drifting, and nucleation and texture enhancement of the overlying Cu film. Metallic tantalum is a very promising candidate. In this paper, the thermal stability of Cu/Ta interfaces is investigated to estimate the reliability of such a Ta underlayer.
Thin Cu and Ta films were consecutively deposited without breaking vacuum using a dc sputtering method to simulate the seed layer and underlayer in a Cu metallization structure. All the synthesized Ta films were the metastable tetragonal structure rather than the stable body-centered cubic (bcc) phase.
We have shown that (111) Cu grows epitaxially on top of (002) tetragonal Ta even though the Cu and Ta have hexagonal and tetragonal atomic arrangement on those planes, respectively. Using electron diffraction in cross-sectional and plan-view samples, an unexpected atomic matching at the interface was discovered as shown in Figure 1(b).
Structure Determination Of The Al2cumg Intermetallic Phase
Authors: Radmilovic V , Kilaas R , Dahmen U 
Published: July 2020

Abstract
The mechanical properties of Al-Cu-Mg alloys depend on a dispersion of Al2CuMg phase precipitates which form as laths along &lt;100&gt;A1, with {012}A1 as the habit plane. Despite extensive study, the crystal structure, morphology and interface structure between the Al2CuMg intermetallic phase and the Al matrix are still not well understood. Since the mechanical behavior of Al alloys strengthened by the S-phase cannot be controlled without a clear understanding of its crystallography and interface structure, the goal of this investigation was to characterize the crystal structure, evolution and interface structure of the S-phase using quantitative electron beam characterization techniques. Several models have been proposed for the crystal structure of Al2CuMg. A widely accepted model of the S-phase was given by Perlitz and Westgren (PW) [1], shown in Fig. 1. The unit cell of the PW model is orthorhombic with unit cell dimensions a = 0.4 nm, b = 0.923 nm, and c = 0.714 nm, space group Cmcm, containing 16 atoms in the ratio Al:Cu:Mg = 2:1:1.
Encapsulated Fullerenes Within Single Wall Carbon Nanotubes
Authors: Smith Brian W , Luzzi David E 
Published: July 2020

Abstract
It is well documented that the pulsed laser vaporization of graphite produces both carbon nanotubes and C60 in the presence of certain metallic catalysts. In nanotube production most of the Ceo is removed along with other residual contaminants during succeeding purification and annealing steps. The possibility of C60 becoming trapped inside a nanotube during this elaborate sequence has been considered but not previously detected.
Nanotubes are observed with high resolution transmission electron microscopy under conditions chosen to minimize both exposure time and irradiation damage. Since a nanotube satisfies the weak phase object approximation, its image is a projection of the specimen -potential in the direction of the electron beam. The image has maximum contrast where the beam encounters the most carbon atoms, which occurs where it is tangent to the tube’s walls. Thus, the image consists of two dark parallel lines whose separation is equal to the tube diameter, 1.4 nm.
Mesostructure Of Pd And Pt Nanoclusters Chemically Stabilized With Phosphide And Phenanthroline Ligands: Hrtem And Aem Characterization
Authors: Oleshko Vladimir P , Crozier Peter A , Schryvers Nick , Vargaftik Michail 
Published: July 2020

Abstract
The noble metal (Me = Au, Pd, Rh, and Pt) polynuclear coordination compounds of Chini’s type eventually serve as a remarkable bridge between molecular clusters and metal colloids. The sizes of the metal cores of the cluster compounds are close to lower sizes of colloidal metal particles. However, chemically stabilized nanoclusters have a distinct ligand environment with a definite stoichiometry inherent to molecular clusters. Interest in structures of the cluster compounds has increased in recent years in view of their unique selective catalytic properties under mild conditions, which, in principle, open a way to the development of a new branch of catalysis by metal clusters, quantum-size effects in the thermodynamic properties, and applications as nano-sized electronic devices (quantum dots). A key feature in structural characterization of such species (they are amorphous solids usually unsuitable for x-ray diffraction analysis) is to understand the relations between the atomic arrangement, electronic structure and chemical reactivity.
Morphological Variations Of Nano-Scale Powder And Deposits Of Ain Produced By Vapor Phase Synthesis
Authors: Di lello BC , Moura F J , Solόrzano I G 
Published: July 2020

Abstract
Aluminum Nitride (AIN) has arised as a promising synthetic material, valued for its high thermal conductivity coupled with high electrical resistivity. These properties, associated with the fact that AIN is nontoxic and has thermal expansion characteristics which closely match those of silicon, makes it an excellent material for electronic packaging. Currently two commercial processes are primaly used for the manufacture of AIN powder, the direct nitridation of the metal, and the carbothermic reduction of the alumina in the presence of nitrogem.
In this work, nanosized aluminum nitride particles were synthesized from the phase using ammonia and aluminum chloride vapor as reactants. This system consists of a vaporization system, ammonia (NH3) distributor, tubular synthesis reactor and powder collection system. The aluminum chloride (AlCl3) vapor starts to react with ammonia injected in the synthesis reactor inlet position (mixing zone). The aluminum nitride nucleates and grows along the reactor length. The aluminum nitride powder produced was collected and chemically and physically characterized.
Image Simulation of Solid Xe Layers at an Interface of a Liquid Xe Inclusion and an Al matrix
Authors: Fujii T , Dahmen U , Johnson E , Birtcher RC , Donnelly SE , Allen C W 
Published: July 2020

Abstract
Xe inclusions can be formed in an Al matrix by ion implantation. The inclusion size and state (solid, liquid or vapor) can be controlled by changing the total ion dose and implantation temperature. Inclusions below about 10nm in size have been reported to be solid with a face centered cubic structure and a lattice parameter of about 0.6nm. Small solid inclusions have cuboctahedral shapes bounded by {111} and to a lesser extent by {100} facet planes. Larger liquid inclusions maintain their facets on the {111} planes of Al but the {100} facets become rounded. It is found that high resolution images of these liquid Xe inclusions exhibit an unusual contrast effect similar to that previously observed for liquid Pb inclusions in Al. This contrast is limited to the {111} facets and could indicate the presence of a thin solid layer of Xe. In this work we investigate the origin of this contrast effect by HRTEM observation and image simulation.
Nanosized Xe precipitates were formed in an Al matrix by ion implantation with 35 keV Xe at 474K to a dose 5×1015 ions/cm2. Through focus series of high resolution electron micrographs in the &lt;110&gt; zone axis orientation were taken on the Berkeley ARM-1000 at an accelerating voltage of 800kV.