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In this work, we compare the results of different Cliff–Lorimer (Cliff & Lorimer 1975) based methods in the case of a quantitative energy dispersive spectrometry investigation of light elements in ternary C–O–Si thin films. To determine the Cliff–Lorimer (C–L) k-factors, we fabricated, by focused ion beam, a standard consisting of a wedge lamella with a truncated tip, composed of two parallel SiO2 and 4H-SiC stripes. In 4H-SiC, it was not possible to obtain reliable k-factors from standard extrapolation methods owing to the strong CK-photon absorption. To overcome this problem, an extrapolation method exploiting the shape of the truncated tip of the lamella is proposed herein. The k-factors thus determined, were then used in an application of the C–L quantification procedure to a defect found at the SiO2/4H-SiC interface in the channel region of a metal-oxide field-effect-transistor device. As in this procedure, the sample thickness is required, a method to determine this quantity from the averaged and normalized scanning transmission electron microscopy intensity is also detailed. Monte Carlo simulations were used to investigate the discrepancy between experimental and theoretical k-factors and to bridge the gap between the k-factor and the Watanabe and Williams ζ-factor methods (Watanabe & Williams, 2006).

Closed form analytical equations used to calculate the collection solid angle of six common geometries of solid-state X-ray detectors in scanning and scanning/transmission analytical electron microscopy are presented. Using these formulae one can make realistic comparisons of the merits of the different detector geometries in modern electron column instruments. This work updates earlier formulations and adds new detector configurations.

A previously developed Monte Carlo code has been extended to the X-ray microanalysis in a (scanning) transmission electron microscope of plan sections, consisting of bilayers and triple layers. To test the validity of this method for quantification purposes, a commercially available NiOx (x ∼ 1) thin film, deposited on a carbon layer, has been chosen. The composition and thickness of the NiO film and the thickness of the C support layer are obtained by fitting to the three X-ray intensity ratios I(NiK)/I(OK), I(NiK)/I(CK), and I(OK)/I(CK). Moreover, it has been investigated to what extent the resulting film composition is affected by the presence of a contaminating carbon film at the sample surface. To this end, the sample has been analyzed both in the (recommended) “grid downward” geometry and in the upside/down (“grid upward”) situation. It is found that a carbon contaminating film of few tens of nanometers must be assumed in both cases, in addition to the C support film. Consequently, assuming the proper C/NiOx/C stack in the simulations, the Monte Carlo method yields the correct oxygen concentration and thickness of the NiOx film.

There is a fairly old apocryphal quotation stating : “Everything that can be invented has been invented.” [1] attributed at one time to Charles H. Duell of the US Patent office in 1899. We all realize this is an absurd statement, and it is well documented that Duell actually said something quite different and urged the US Congress to encourage the advancement of science as well as to improve the patent system [2,3]. This does however bring to focus a salient point concerning x-ray spectroscopy, as it relates to analytical electron microscopy. For many years instrument developers have concentrated upon advances in electron-optics, with justifiable and demonstrated improvements in imaging and probe forming systems. Aberration correctors, high sensitivity imaging detectors and electron spectrometry systems abound [4] , however, there are only a few seminal events which mark evolutionary advances in x-ray spectrometry. Arguably we can list the foremost of these as: the invention of electron microprobe analysis (EMPA) by Castaing [5], the invention of the Lithium Drifted Silicon (Si(Li) solid state detector [6], the development of the first AEM (EMMA-4) [7] and the development of the Silicon Drift Detector (SDD)[8]. While these are all key events which mark the onset of major advances in our ability to perform microanalysis, by comparison they represent only a fraction of the investment in resources compared to the electron optical developments. A very large fraction of the instrumentation found in characterization facilities worldwide has ancilliary x-ray analysis subsystems. The majority of these ancilliary x-ray spectrometry systems have been interfaced to an electron optical column in the simplest possible configuration and although they are at times considered routine, this does not mean that we have achieved all that these resources can provide, nor does it mean that we have addressed fully all their methodological intricacies and/or potentials.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

The microstructure of a contiuous cast Al alloy was characterized with transmission and scanning transmission electron microscopy, as well as x-ray microanalysis. Several precipitate phases were identified as a function of prior thermomechanical treatment in order to understand the improvement of fatigue properties resulting from those treatments.

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at the Pre-Meeting Congress: Materials Research in an Aberration-Free Environment, at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, July 31 and August 1, 2004.

The electron beam broadening in specimens is a important issue to obtain a high spatial resolution expected by using a fine electron probe of nanometer order in analytical electron microscopy. Beam broadening mainly depends on electron diffusion in specimens. The theoretical equation on the beam broadening, which is based on single scattering approximation model for incident electrons, has been proposed by Goldstein et al.. in this work, the beam broadening was estimated experimentally by a TEM equipped with a field emission gun and the results were compared with the values theoretically obtained.The sizes of the beam diameter with and without specimens were measured by using JEM-2010F and JEM 3000F TEMs, which are equipped with a field emission gun, being operated at 200 and 300 kV, respectively. The beam diameter was defined as the diameter containing 90% of the total electrons. The specimens used were amorphous SiO2, crystalline MgO and Si.

An important aspect in the consideration of V-4%Ti-4%Cr alloys as structural materials for proposed fusion reactors, especially for weldments, is the sensitivity of mechanical behavior to oxygen content. Following a 1-h anneal at 1200°C, sheet specimens were subjected to extended (16h to 43h) anneals at 500°C in 5 to 8 x 10-6 torr oxygen, followed by an homogenization vacuum anneal of 100 h at 600°C. Weight gains indicated ∼200 to >1400 wppm oxygen doping. Specimens were also subjected to an additional vacuum anneal for 4 h at 950°C. Specimens were prepared by standard double-jet electropolishing for TEM characterization with a Philips CM30 (LaB6) equipped with a Gatan Imaging Filter (GIF), and with a Philips CM200FEG equipped with Oxford EDS, GIF, and Emispec Vision integrated acquisition system.Following oxygen doping and homogenization, high concentrations of nanoscale G.P.-zone-like clusters on ﹛001﹜ were observed in the matrix, with a ∼200-nm-wide precipitate free zone (PFZ) at grain boundaries.

The fiber/matrix interfaces play a critical role in the mechanical performance of fiber-reinforced ceramic-matrix composites (CMCs). In this vein, the placement of an interphase material between the fiber and matrix phases has received considerable attention. The main purpose of the interphase coating is to enhance toughness of the composite by influencing crack trajectories at the mechanically critical (weak) fiber/coating interface.This interest in coated-fiber composites has been accompanied by the need for accurate microanalysis of the CMC systems, owing to issues of both morphological and chemical incompatibilities between the dissimilar fiber and coating materials. Consequently, microanalysis has been driven below the micrometer scale, into the length scale of nanometers. Thus, the examination of the fiber/coating interfaces in CMCs falls squarely into the realm of transmission electron microscope (TEM) and scanning transmission electron microscopy (STEM) analyses.However, the success of TEM/STEM-based microanalysis of CMCs hinges critically on the quality of TEM specimen.

An oxidation resistant interfacial layer between the fiber and the matrix is important for prolonged use of ceramic-matrix composites (CMC). The interface layer has to be chemically compatible and stable in high temperature oxidizing environments. At present various oxide based interface layers in CMC are being considered. One candidate is porous interfaces. Zircon has good thermomechanical stability with SiC and mullite, and resists pore coarsening, so it is of interest as a porous interface materials.Ethanolic zirconia and silica precursors, complexed with polyelectrolytes to form fugitive carbon for porosity were doped with vanadium. These were used to continuously coat the 3M Nextel 720™ alumina-mullite fibers. These fibers were heat-treated in-line in argon at 1000-1300°C, with the aim of finding heat-treatment conditions that would convert the zirconia, silica, and polyelectrolyte into a fine mechanical mixture of zircon and carbon.

Advances in energy-dispersive detector technology were largely responsible for electron probe microanalysis (EPMA) becoming a valuable tool for biologists, while development of EPMA received much impetus from the special needs of biological research. Solid-state energy-dispersive detectors placed in close proximity to specimens in transmission electron microscopes (TEMs) provided the necessary geometric detection efficiency, hence sensitivity and higher spatial resolution, and the reasonably good energy resolution of these detectors permitted reliable separation of overlapping peaks, such as the Kαpeak of the biologically important messenger, calcium, and the Kβpeak of another, biologically much more abundant element, potassium. Improvements in the pole-piece design of TEMs to allow closer access of the X-ray detector to the specimen and interfacing the software of one company with detectors provided by another also helped progress, and EPMA, in conjunction with rapid freezing of cells, was ready to address important biological problems, such as the dynamics of the composition of intracellular organellesin situ.