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Calcium (Ca) oxalate crystals occur in many plant species and in most organs and tissues. They generally form within cells. A number of techniques exist for the identification of crystals: X-ray diffraction, Raman microprobe analysis and infrared spectroscopy are the most accurate. The isolation and crystallochemical characterization of calcium oxalate crystals in the leaves of Amaranthus tricolor scion Valentina was studied. Anatomical features and chemical composition of the inclusions was studied by EDS, combined with an analytical scanning electron microscope. On the transverse sections of the amaranth leaves and in the veins of the leaf, multiple crystals of circular shape were found. EDX analysis revealed 4 elements in the crystal - Mg, P, K and Ca. The characteristic energy spectra of X-ray radiation emitted by the element K, P and Ca were studied. The combination of SEM and EDX was a convenient method for determining the mineral inclusions of the cross-section leaves of Amaranthus L.

An automatized channel for measuring the resistivity in materials by the four-point probe technique was developed. The installation was based on Cascade Microtech MPS150 microprobe station, National Instruments PXIe-4143 power supply unit and PXI-4072 digital multimeter. Registration modes of surface and bulk specific resistance for samples with positioning the probes in a line or at square vertices were implemented. Measurements under corresponding modes were carried out for metallic, semiconducting bulk samples and thin coatings. Conductive and optical properties of 10, 20 and 30 nm Au layers formed on quartz glass by magnetron sputtering were investigated.

A large refurbishment started in 2013 with the aim of upgrading the focusing optics of the LNLS D09B-XRF beamline. Today, the beamline comprises a new X-ray microfocusing optic based on a pair of bendable mirrors in the Kirkpatrick-Baez arrangement. The upgrading strategy also involved the migration of the control system to a NI PXI system (National Instruments Corporation), integrated with an open source EPICS/Linux platform. A new approach using a PXI system as a hardware triggering interface was developed in order to provide a continuous scanning mode of operation (”on-the-fly” scans) at D09B-XRF beamline. In this work, the main features of the LNLS XRF microprobe station as well as a description for setting up a general approach for fast scanning mode operation will be presented.

Using the method of microprobe analysis and transmission electron microscopy, the influence of obtaining conditions upon particular elemental composition and growth structure coatings of Ti–Al–Si–Mo–S–N system was studied. The possibility of formation and characteristics of the structural and elastic-stress state single-layer coatings with nanoscale columnar or equiaxed grains and gradient-layered, combining two types of selected structure, was defined. On the basis of hardness, tribological properties and coating hardness, a conclusion was made about the relative prospects of its use as wear-resistant coatings with a nanocrystalline structure.

An extensive process of modernizing the research infrastructure started 6 years ago at the tandem accelerator in IFIN-HH. Major improvements of the 9 MV FN tandem accelerator installed in IFIN-HH in ′73 were done in the late years, making it a very reliable machine, suited for basic and applied research experiments. The developments opened the way for new experiments made for the first time in our laboratory. Two new Cockroft-Walton tandem accelerators were also installed in 2012. The 1 MV HVE Tandetron accelerator is dedicated to AMS measurements, especially for 14C dating, while the 3 MV HVE Tandetron accelerator has the reaction chambers and detection system prepared for ion beam analysis measurements, microprobe experiments and ion implantation.

The Ion Beam Modification and Analysis Laboratory (IBMAL) at the University of North Texas includes several accelerator facilities with capabilities of producing a variety of ion beams from tens of keV to several MeV in energy. The four accelerators are used for research, graduate and undergraduate education, and industrial applications. The NEC 3MV Pelletron tandem accelerator has three ion sources for negative ions: He Alphatross and two different SNICS-type sputter ion sources. Presently, the tandem accelerator has four high-energy beam transport lines and one low-energy beam transport line directly taken from the negative ion sources for different research experiments. For the low-energy beam line, the ion energy can be varied from ∼20 to 80 keV for ion implantation/modification of materials. The four post-acceleration beam lines include a heavy-ion nuclear microprobe; multi-purpose PIXE, RBS, ERD, NRA, and broad-beam single-event upset; high-energy ion implantation line; and trace-element accelerator mass spectrometry. The NEC 3MV single-ended Pelletron accelerator has an RF ion source mainly for hydrogen, helium and heavier inert gases. We recently installed a capacitive liner to the terminal potential stabilization system for high terminal voltage stability and high-resolution microprobe analysis. The accelerator serves a beam line for standard RBS and RBS/C. Another beamline for high energy focused ion beam application using a magnetic quadrupole lens system is currently under construction. This beam line will also serve for developmental work on an electrostatic lens system. The third accelerator is a 200 kV Cockcroft-Walton accelerator with an RF ion source. The fourth accelerator is a 2.5 MV Van de Graaff accelerator, which was in operation for last several decades is currently planned to be used mainly for educational purpose. Research projects that will be briefly discussed include materials synthesis/modification for photonic, electronic, and magnetic applications, surface sputtering and micro-fabrication of materials, development of high-energy ion microprobe systems, and educational and outreach activities.

The aim of the study was to develop a fast and simple method for preparation of polycrystalline Mg2Si. For this purpose a Spark Plasma Sintering (SPS) method was used and synthesis conditions were adjusted in such a manner that no excess Mg was required. Materials were synthesized by the direct reaction of Mg and Si raw powders. To determine the phase and chemical composition, the fabricated samples were studied by X–ray diffraction and SEM microscopy coupled with EDX chemical analysis. Thermoelectric properties of samples (thermal conductivity, electrical conductivity and Seebeck coefficient) were measured all over temperature range of 300–650 K. The analysis by the scanning thermoelectric microprobe (STM) shows that samples have uniform distribution of Seebeck coefficient with mean value of about −405 μVK−1 and standard deviation of 94 μVK−1. Prepared materials have intrinsic band gap of 0.45 eV and thermal conductivity λ = 7.5 Wm−1K−1 at room temperature.

High efficiency segmented thermoelectric unicouples STUs made of Bi2Te3 and CoSb3-based alloys have been developed. The performance parameters of elements at selected temperatures ranging from 288 to 673K were tested on the constructed set-up. Characterization of electrical resistances of contacts and materials was made by a scanning thermoelectric microprobe (STM). The extended numerical model of STU, which takes into account i.e. thermal resistances and thermoelectric effects at junctions, as well as, inside segments (Thomson effect) was developed. The results of numerical calculations were compared with experimental data.

We report commissioning of the microprobe-XRF beamline on Indus-2 synchrotron source. The beamline has been recently made operational and is now open for the user's experiments. The beamline comprises of Si(111) double crystal monochromator and Kirkpatrick-Baez focusing optics. The beamline covers wide photon energy range of 4 – 20 keV using both collimated and micro-focused beam modes. The design details and the first commissioning results obtained using this beamline are presented.

For the analysis of certified semiconducting Al0.7Ga0.3As/GaAs superlattices and photovoltaic samples, we used new generations Auger nano‐probes such as the JEOL JAMP‐9500F Field emission Microprobe and the PHI‐700 Xi system. These nano‐probes are generally used for the chemical analysis of complex nano‐structures at the deca‐nanometric scale. In this paper, we first used both systems for the determination of the surface composition of an Al0.7Ga0.3As/GaAs reference sample. In that, we studied the impact of surface topography on the Auger analysis. Secondly, we used both systems for chemical analysis of photovoltaic samples. Here, we investigated the in‐depth chemical composition, in particular the a‐Si:H (n)/ZnO/Al and ITO/a‐Si:H (p) interfaces, after a specific cross‐section preparation. However, limitations such as image drift due to acoustic vibration and heating effects due to continuous bombardment of energetic electrons at the same point are still a big challenge for quick, routine analysis.

An x‐ray microprobe system with total‐reflection mirror optics for trace element analysis has been developed at beamline 37XU of SPring‐8. To achieve sub‐microprobe, a spatial filter has been installed downstream of a monochromator. Focusing tests have been performed in the x‐ray energy range of 6–14 keV. A focused beam size of 0.83 μm(V)×1.35 μm(H) has been obtained at an x‐ray energy of 10 keV, and using a spatial filter in the horizontal direction, the beam size is down to 0.84 μm. Micro‐x‐ray absorption fine structure (XAFS) spectroscopy of submicrometer particles has been done by utilizing the total‐reflection mirror optics. It was clearly observed from the nickel K‐edge XAFS spectra that the oxidation state of nickel was a mixture of metal and oxide even in the single submicrometer particle.

Encouraged by our recent x‐ray fluorescence microprobe analysis revealing subcellular metal relocation in two special cell types, we are working to identify the role of zinc and copper in these cells. In verifying that metal ion dynamics are not artifactual, particularly where some samples have been chemically fixed, a comparison of our past results with samples studied with cryofixation and immunofluorescence add validation to our previous findings. Our work demonstrating cryofixation in human microvascular endothelial cells and metallothionein immunofluorescence in stem cells is presented.

A prominent feature of soil colloids is their huge specific surface. It determines colloidal properties such as adsorption capacity or diffusion. The colloidal interactions differ significantly from the behavior of the same materials in a bulk system. Interactions in the colloidal regime are crucial, for example, for the transport and release of nutrients and toxicants in soils, which then influences directly the growth of plants. However, there is still a need for more analytical resources to study those interactions. To reveal the correlation of the particular trace elements and their distribution in correlation to colloidal interactions as well as changing pH values, experiments at the hard x‐ray fluorescence microprobe at beamline 2‐ID‐E of the Advanced Photon Source (APS), were performed with colloidal clay and soil samples in an aqueous environment as naturally relevant. To obtain further spatial information, stereo imaging has been used. To study the dynamical behavior of these colloidal suspensions at changing pH, a wet sample chamber allowing in situ manipulation was developed and utilized.

The MicroAnalysis Toolkit is an analysis suite designed for the processing of x‐ray fluorescence microprobe data. The program contains a wide variety of analysis tools, including image maps, correlation plots, simple image math, image filtering, multiple energy image fitting, semi‐quantitative elemental analysis, x‐ray fluorescence spectrum analysis, principle component analysis, and tomographic reconstructions. To be as widely useful as possible, data formats from many synchrotron sources can be read by the program with more formats available by request. An overview of the most common features will be presented.

The Soft X‐ray Micro‐characterization Beamline (SXRMB) is a medium energy, bending magnet based beamline, designed to cover an energy range of 1.7–10 keV using two sets of crystals—InSb(111) and Si(111). The design goal is to deliver a flux of 2×1011 photons sec−1/100 mA with a resolution up to 10,000 for X‐ray Absorption Spectroscopy. A KB mirror stage is designed to provide microprobe capability, with a spot size of 10×10 μm2 and a flux of >109 at the microprobe station. The beamline has been in the commissioning phase since 2008, and access to the X‐ray absorption endstation is now open to general users. The optical commissioning and performance of the beamline is presented with some early experimental results.

VESPERS beamline is a hard X‐ray microprobe beamline at the Canadian Light Source (CLS). It is designed to measure material structure and composition using X‐ray diffraction (XRD) and X‐ray fluorescence (XRF) spectroscopy. Four widely differing bandwidths, ∼0.01%, ∼1.6%, ∼10%, and fully polychromatic beam, are selectable to simplify the Laue diffraction analysis and to optimize XRF excitation. Also, X‐ray absorption spectroscopy (XAS) can be employed using ∼0.01% bandwidth to provide chemical analytical information. Currently, the beamline is in its late commissioning phase. A number of test experiments have been performed to show the Laue XRD, XRF and XAS capabilities of the beamline. Beamline control and data acquisition software have been developed to include the essential functions for user operation. Full user operation starts in 2010.

An instrument for hard X‐ray magnetometry with spatial and time resolutions of 400‐ps and sub‐2‐μm was developed at BL39XU, SPring‐8.The technique is based on X‐ray magnetic circular dichroism measurements combined with KB focusing mirrors and a fast current source, which generates a pulsed magnetic field of 400‐ps duration that is synchronized with the X‐ray pulses provided from the storage ring in the 203‐bunch operation (42 MHz) with a jitter of 50 ps. By fully using the bulk‐sensitivity and element‐specificity of hard X‐ray dichroism, we have demonstrated that the magnetization reversing process in the nanosecond time scale of the free NiFe and pinned CoFeB/CoFe layers were separated in a 10‐μm dot sample with a NiFe/MgO/CoFeB/CoFe/MgO structure mimicking a magnetic tunnel junction device.

The effect of titanium particle morphology on the shock sensitivity of titanium‐silicon powder mixtures has been investigated experimentally. The powder mixtures were tested in a planar recovery capsule, with the shock loading produced by a high explosive booster charge placed on top of the capsule and a PMMA attenuator. Reactions were not observed for equimolar mixtures of large (95 μm) spherical Ti particles with fine (15 μm) Si particles for incident peak shock pressures of up to 23 GPa, estimated with LS‐DYNA. In contrast, mixtures with fine (40 μm) spherical Ti particles or irregularly‐shaped fine (31 μm) Ti particles exhibited a threshold attenuator thickness, and hence shock pressure, for reaction initiation. Microscopy and microprobe backscatter analysis were used to identify the degree of intermixing between the particles for shock loading just below the reaction threshold. For the largest spherical Ti particles, little particle intermixing was evident. For the finer particles, penetration of Si ...

Selected material from the lunar surface (Luna 16, 20, 24 missions) was investigated using a combination of CL microscopy and spectroscopy with locally resolved microanalytical methods (Micro‐Raman, microprobe, SEM, PIXE) to get information about the mineralogy and the luminescence behavior. Although the general high iron content of most lunar minerals and rocks prevents luminescence activation, certain species on the moon show visible CL. The dominant luminescent minerals are plagioclases and minerals of the SiO2 group, but K‐feldspar, zircon and Ca‐phosphates show also CL emissions. The application of CL imaging reveals microtextures such as zonation, brecciation or deformation features, which are not discernable by other analytical methods. Spectral CL measurements show that the main luminescence activators in lunar minerals are structural defects, Mn2+, REE3+ and Fe3+. The results show principle similarities with terrestrial material but also significant differences (e.g., mineral association, no weat...

The analytical techniques based on ion beams or IBA techniques give quantitative information on elemental concentration in samples of a wide variety of nature. In this work, we focus on PIXE technique, analyzing thick target biological specimens (TTPIXE), using 3 MeV protons produced by an electrostatic accelerator. A nuclear microprobe was used performing PIXE and RBS simultaneously, in order to solve the uncertainties produced in the absolute PIXE quantifying. The advantages of using both techniques and a nuclear microprobe are discussed. Quantitative results are shown to illustrate the multielemental resolution of the PIXE technique; for this, a blood standard was used.

The microenvironment at and adjacent to surfaces of actively metabolizing cells, whether in a planktonic state or adhered to mineral surfaces, can be significantly different from the bulk environment. Microbial polymers (polysaccharides, DNA, RNA, and proteins), whether attached to or released from the cell, can contribute to the development of steep chemical gradients over very short distances. It is currently difficult to predict the behavior of contaminant radionuclides and metals in such microenvironments, because the chemistry there has been difficult or impossible to define. The behavior of contaminants in such microenvironments can ultimately affect their macroscopic fates. We have successfully performed a series of U LIII edge x‐ray absorption fine structure (XAFS) spectroscopy, hard x‐ray fluorescence (XRF) microprobe (150 nm resolution), and electron microscopy (EM) measurements on lepidocrocite thin films (∼1 micron thickness) deposited on kapton films that have been inoculated with the dissimilatory metal reducing bacterium Shewanella oneidensis MR‐1 and exposed to 0.05 mM uranyl acetate under anoxic conditions. Similarly, we have performed a series of U LIII edge EXAFS measurements on lepidocrocite powders exposed to 0.05 mM uranyl acetate and exopolymeric components harvested from S. oneidensis MR‐1 grown under aerobic conditions. These results demonstrate the utility of combining bulk XAFS with x‐ray and electron microscopies.

Since 2004 ISAS operates a dipole beamline at the synchrotron radiation facility DELTA at University of Dortmund. Synchrotron radiation is used at this beamline as an excellent excitation source for X‐ray fluorescence spectrometry (XRF). Among others, the high brilliance of the synchrotron radiation in contrast to conventional X‐ray tubes, the strong polarization of the synchrotron radiation and the low divergence of the electron beam can be applied to XRF offering several advantages for spectroscopy. These outstanding features encouraged us to develop and operate a synchrotron radiation induced X‐ray micro fluorescence probe connected to a wavelength dispersive spectrometer (SR‐WDXRF). A relevant characteristic of such a device, namely, good lateral resolution at high spectral resolution can be applied for single spot‐, line‐scan and area map analyses of a variety of objects. The instrumentation of the SR‐WDXRF and the performed experiments will be presented. Main task is the detection of light elements ...

The CLS 06ID‐1 Hard X‐ray Micro‐Analysis Beamline (HXMA) is a general purpose hard X‐ray spectroscopy beamline (5 to 40 keV) designed to serve users in XAFS, diffraction and microprobe communities. The beamline uses the synchrotron radiation from a superconducting wiggler. The primary beamline optics include a 1.2 m water‐cooled silicon collimating mirror (separate Rh and Pt coating stripes), a liquid nitrogen cooled double crystal monochromator (Kohzu CMJ‐1) housing two crystal pairs (Si 111 and 220), and a 1.15 m long water‐cooled silicon toroidal focusing mirror (separate Rh and Pt coating stripes). All mirrors are equipped with dynamical meridian benders. The experimental hutch hosts three experimental setups for XAFS, diffraction and microprobe, respectively. Primary design considerations and some commissioning results are discussed.

Nuclear microscopy is one of the most powerful tools which are able to determine quantitative trace element distributions in complex samples on a microscopic scale. The advantage of nuclear microprobes are that different ion beam analytical techniques, like PIXE, RBS, STIM and NRA can be applied at the same time allowing the determination of the sample structure, major, minor and trace element distribution simultaneously.In this paper a nuclear microprobe setup developed for the microanalysis of thin complex samples of organic matrix at the Debrecen Scanning Nuclear Microprobe Facility is presented. The application of nuclear microscopy in life sciences is shown through an example, the study of penetration of TiO{sub 2} nanoparticles of bodycare cosmetics in skin layers.

Canadian Light Source Hard X‐ray Micro‐Analysis Beamline (HXMA, 06ID‐1) is a hard X‐ray spectroscopy beamline currently under commissioning. The source of the beamline is a superconducting wiggler covering 5 to 40 keV. The primary optics include a cryogenically cooled double crystal monochromator (Si 111 and 220), white beam vertical collimating and toroidal focusing mirrors. End station experimental capabilities include XAFS (Ge solid state detectors), microprobe (Kirkpatrick‐Baez murors, Ge solid state detector and image plate area detector), and diffraction (Huber psi‐8 and powder diffraction setups, with diamond anvil cell high pressure sample environment). Commissioning status for the XAFS capabilities is described.

We have incorporated differential phase‐contrast (DPC) detection in a hard x‐ray fluorescence microprobe at the Advanced Photon Source. We report a straightforward implementation of unidirectional DPC and demonstrate that it is highly advantageous for imaging low‐Z specimens with hard x‐rays (10keV). Phase‐contrast imaging of a specimen can be used to acquire fast overview images of samples that allow more precise targeting of time consuming fluorescence scans. In order to get an overview of the elemental content of a specimen in these fly‐scans, we have also implemented a fast detection of total fluorescence yield. Additionally, a DPC image of the specimen is obtained simultaneously with the fluorescence maps in normal step‐scanning mode, to facilitate a direct comparison and co‐registration with visible light micrographs.

The hard X‐ray microprobe provides an effective methodology for the non‐destructive analysis of inhomogeneous materials. Application of X‐ray absorption/fluroescence spectroscopy techniques (XANES and EXAFS) permits the speciation of the elements and yields information about the local structural environment. Microfocussed, monochromatic, tunable X‐rays allows examination of small areas of micrometer dimensions with spectroscopic procedures. Typically the materials which are presented are thick and cannot be altered for the experiment. This condition introduces difficulties which may compromise the results. Herein we discuss those difficulties and show that the system can yield reliable results in spite of the compromises. Some results are presented on the two iron meteorites we have examined. These specimens are representative of highly inhomogeneous materials and illustrate the difficulties encountered with compositional variations which may occur at sub‐millimeter dimensions and also illustrate the difficulties presented by the need to analyze components present at ppm concentration levels in a concentrated matrix. In these particular samples the major constituent is Fe which ranges from 90% to 70%, balanced by Ni which ranges from 10% to 30%. The critical diagnostic trace elements Ga and Ge which must also be analyzed are present at the 80 and 340 ppm level respectively. These diagnostic elements have been shown by EXAFS to be substitutionally placed in the matrix of the major element species in these meteorite samples.

Microfocusing experiments of high‐brilliance, high‐energy X‐ray by using a multilayer Fresnel zone plates were performed at SPring‐8. It is proved that the multilayer FZPs can be used as focusing elements with high spatial resolution in a wide range X‐ray wavelength domain up to 100 keV. A Cu/Al FZP with the thickness of 40 micron has attained the spatial resolution of 0.7 ∼ 1.8 micron in a wide range X‐ray wavelength domain of 18.6 ∼ 113 keV. Three types of microscopic image of an Au mesh with 1500 lines per inch were taken by a X‐ray microscopy experiment by using the multilayer FZP at 82 keV: a scanning microscopic transmission image, a scanning microscopic fluorescent one and an imaging microscopic one with the spatial resolution of ∼ 0.7 micron. High‐energy X‐ray microprobe by using the multilayer FZP will be powerful tool for non‐destructive various analyses of thick materials (bulk, IC, etc) with submicron spatial resolution.

Micro‐scale Proton‐induced X‐ray Emission (PIXE) of trace elements (TE) in sulfides provides insights into geologic processes including magmatic system evolution, ore forming events, and fluid‐flow processes. The Los Alamos nuclear microprobe was used to determine TE concentrations and ratios in sulfides from diverse geologic environments including hydrothermal ore deposits, coal seams, and metamorphic rocks. Pyrrhotite (Po) from silicic volcanics contains high Cu and Ni; Po from the Clear Lake volcanic field has higher Mo than does Po from other volcanic fields. Coal pyrites contain high Cu, As, Se, Mo and Pb, and show high As/Se and Mo/Se in marine influenced sulfides from the Lower Kittanning coal, but not in other marine‐influenced coals. Sulfides are amenable to micro‐PIXE studies because of the difficulties in obtaining the homogeneous standards required for many other TE microanalytical techniques.

The number of nuclear microprobe setups is growing steadily and its potential in research fields such as biomedicine, material science and geology is being established. The most existing microprobe lenses can focus a proton beam up to energy of 30 MeV. The studies reported here deal with magnetic quadrupole systems such as Russian Separated Quadruplet for obtaining 3–150 MeV proton microbeams. For a given magnetic field in the quarupole lenses optimal parameters of microprobes for different energies of protons are obtained. The smallest beam spot size and appropriate geometry of the focusing and matching slit systems have been found for three different emittances.

This work is an application of synchrotron microprobe X‐ Ray fluorescence in order to study elemental distribution along human hair samples of contemporary citizens. Furthermore, X‐Ray fluorescence spectrometry is also used to analyse human bones of different historical periods: Neolithic and contemporary subjects. The elemental content in the bones allowed us to conclude about environmental contamination, dietary habits and health status influence in the corresponding citizens. All samples were collected post‐mortem. Quantitative analysis was performed for Mn, Fe, Co, Ni, Cu, Zn, Br, Rb, Sr and Pb. Mn and Fe concentration were much higher in bones from pre‐historic periods. On the contrary, Pb bone concentrations of contemporary subjects are much higher than in pre‐historical ones, reaching 100 μg g‐1, in some cases. Very low concentrations for Co, Ni, Br and Rb were found in all the analysed samples. Cu concentrations, allows to distinguish Chalcolithic bones from the Neolithic ones. The distribution of trace elements along human hair was studied for Pb and the obtained pattern was consistent with the theoretical model, based on the diffusion of this element from the root and along the hair. Therefore, the higher concentrations in hair for Pb of contemporary individuals were also observed in the bones of citizens of the same sampling sites. All samples were analysed directly without any chemical treatment.

The Acadiana Research Laboratory of the University of Louisiana at Lafayette provides high energy ion beams for materials research. Major components of the ion beam systems include a National Electrostatics Corporation (NEC) 1.7 MV tandem Pelletron accelerator system with both SNICS and RF ion sources and a Varian CF-4 200 kV implanter. The NEC Pelletron has three operational beamlines that provide a wide range of capabilities for materials modification and analysis, including such techniques as PIXE, PIGE, RBS, RFS, TOF-ERDA and ion implantation. An Oxford Microbeams Ltd. microprobe system was recently declared operational with the attainment of a 1.5 μm×2.0 μm beam spot size. Microprobe techniques presently available include μPIXE, μRBS and scanning transmission ion microscopy (STIM).

The paper reports the recent progress of a high-energy, heavy ion nuclear microprobe facility established at the University of North Texas. The microprobe system is installed on a 3MV NEC 9SDH-2 Pelletron tandem accelerator. A high demagnification factor (∼60) has been achieved with the system, using a probe-forming lens system (from MARC, Melbourne, Australia) with the new Russian quadruplet configuration. The spatial resolution of 2–3 μm has been achieved for 4.0 MeV carbon ions or 9.0 MeV alpha particles with a beam current of ∼50–100 pA. Better spatial resolution (approaching one μm) is achievable when an extremely low beam current (100–2000 ions/sec) is used in the applications of IBICC and IBIL. Applications of the analytical techniques with the nuclear microprobe are outlined and discussed.

Ion Beam Induced Luminescence (IBIL) and Ion Beam Induced Charge Collection (IBICC) have been used to study the efficiency and the homogeneity of the luminescence emission in phosphors. The IBIL imaging was made by using sharply focused ion beams or broad/partially-focused ion beams. Samples were examined to reveal possible distributed crystal-defects that may lead to the inhomogeneity of the luminescence emission. The purpose of the study is to search for suitable thin films that have high homogeneity of luminescence emission and large IBIL efficiency under heavy ion excitation. These films may be placed as a thin layer on the top of microelectronic devices to be analyzed with Ion Photon Emission Microscopy (IPEM). The emission yields were found to be low for organic materials, due to saturation of the light output dependence on the energy deposition of heavy ions. The emission yield of a typical Bicron plastic scintillator is about 70 photons/ion/micron. Inorganic materials may have higher IBIL yields u...

Nuclear microscopy is usually associated with the use of highly focused MeV ions to measure microscopically the composition of solids. Another use of such focused ions emerged 10 years ago with the introduction of radiation effects microscopy or REM. With REM one exploits the charge deposited by each ion, or the effect of this charge. The power of this new technique stems from the reproducible, and very well understood, linear charge density produced by ions in semiconductors, coupled with the capability of a nuclear microprobe to provide individual ions to a specimen with high spatial resolution. Several techniques form the bases for REM, and these can be categorized under the headings: ion beam induced charge collection (IBICC) and single event effects (SEE) imaging, this paper reviews these techniques, and gives examples of their use in studying charge transport, and the effects of this transport, in semiconductors and integrated circuits.

We describe parabolic compound refractive X-ray lenses made of aluminum that are genuine imaging devices, similar to glass lenses for visible light. When used to image a synchrotron radiation source onto a sample in a strongly demagnifying setup, these lenses allow to produce a small pencil beam of high intensity that can be used for (scanning) microprobe experiments, such as microdiffraction and microfluorescence. The aluminum lenses are most effective above 10 keV and are particularly suited for hard x-rays up to at least 60 keV. The pencil beam has a typical lateral size in the micrometer range with a gain in intensity of two to three orders of magnitude. The small beam convergence in the spot (typically Δk/k

The first part of this paper is devoted to the study of contaminated surface of the uranium materials U, UFe2 and U6Fe a few hours after the preparation. These oxidation conditions are selected with the aim to reproduce the same contamination surfaces that occurred in microprobe analytical conditions. The surface characterization techniques are SIMS and Auger spectroscopy. The contaminated surfaces are described. They are made of successive layers: a carbon layer, one oxidized iron layer followed by an iron depletion layer (only in UFe2 and U6Fe), and a ternary oxide layer (U-Fe-O for UFe2 et U6Fe and UO2+x for the uranium). The second part of this paper is devoted to estimating errors caused by surface contamination during quantitative analysis. EPMA-WDS is used to make the estimation. The analyses were carried out with a CAMECA SX100 and the simulation with the X-Film software.

A Kirkpatrick-Baez micro-focusing system has been implemented at the CAMD X-ray microprobe beamline. The system utilizes gold-coated float glass mirrors at grazing incidence angles that can be varied up to 15 mrad. Dynamically controlled 4-point bending mechanisms are used to approximate elliptical surfaces. The mirrors were characterized for slope error and roughness considerations with regard to the effective focusing based on the source characteristics and geometry. Ordinary float glass blanks were used after a screening process based on slope error. The measured focused spot size compares well with results of ray-tracing and simple geometric optics calculations. The focused spot size is ∼18.8 μm×7.0 μm(σ), with the limiting factor being the size of the CAMD source. Using such a mirror system accommodates operation in both monochromatic and polychromatic (‘white’) modes. The system therefore allows performance of micro-fluorescence measurements using polychromatic light and micro-XANES measurements ove...

Brilliant undulator radiation from a super photon ring 8 GeV (SPring-8) is utilized for spectromicroscopy in hard x-ray region. Design parameters of the x-ray microprobe dedicated for BL39XU are described. X-ray beam less than 1 μm is expected by using a Kirkpatrick and Baez mirror system, and both conventional and high resolution x-ray fluorescence spectrometers are available by using a Si(Li) detector and a wavelength dispersive spectrometer equipped with a flat analyzer crystal and a PSPC. Preliminary experimental results of the x-ray microprobe system show possibilities of trace characterization with spatial resolution.

A hard x-ray scanning microprobe based on zone plate optics and undulator radiation, in the energy region from 6 to 20 keV, has reached a focal spot size (FWHM) of 0.15 μm(v)×0.6 μm(h), and a photon flux of 4×109 photons/sec/0.01%BW. Using a slit 44 meters upstream to create a virtual source, a circular beam spot of 0.15 μm in diameter can be obtained with a photon flux of one order of magnitude less. During fluorescence mapping of trace elements in a single human ovarian cell, the microprobe exhibited an imaging sensitivity for Pt (Lα line) of 80 attograms/μm2 for a count rate of 10 counts per second. The x-ray microprobe has been used to map crystallographic strain and multiquantum well thickness in micro-optoelectronic devices produced with the selective area growth technique.

We have developed a x-ray microprobe in the energy region from 6 to 20 keV using undulator radiation and zone-plate optics for microfocusing-based techniques and applications at a beamline at the Advanced Photon Source (APS). The performance of the beamline was shown to meet our design objectives, including preservation of the source brilliance and coherence, selectable transverse coherence length and energy bandwidth, high angular stability, and harmonic suppression of the beam. These objectives were achieved by careful thermal management and use of a novel mirror and crystal monochromator cooling geometry. All beamline optical components are water cooled, and the x-ray beam in the experiment station is stable in beam intensity, energy, and position over many days with no active feedback. Using a double-crystal Si(111) monochromator, we have obtained a focal spot size (FWHM) of 0.15 μm(v)×1.0 μm(h), and a photon flux of 4×109 photons/sec at the focal spot, and thus a photon flux density gain of 15,000. A...

The scanning photoelectron microscope (SPEM) on beam line 2.2 at the Elettra synchrotron produces small spot XPS spectra from a sub-micron radiation microprobe. It is also capable of producing surface images in terms of the energy resolved photoelectron signal. This microscope has been used to study oxidation on polycrystalline tin and lead surfaces and the variations in reactivity between different crystallite surfaces. The diffusion of gold and silver films on polycrystalline metal surfaces has also been followed.

A new x-ray microprobe beamline was recently installed and commissioned at the Center for Advanced Microstructures and Devices (CAMD), Louisiana State University. Due to the design of the beamline and the end-station, we are able to perform (i) spatially-resolved x-ray fluorescence spectroscopy using the broad intense spectrum of the white synchrotron radiation, and (ii) spatially-resolved x-ray absorption spectroscopy in the energy region of 2000 eV to 12000 eV. The set-up of the beamline and the microprobe end-station, including the Kirkpatrick-Baez focusing system, are described. First focusing experiments show that we achieve a horizontal and vertical focal spot size of 18.8×7.0 microns (σ), respectively, being the limit given by the CAMD source size and demagnification. Initial experimental results featuring white light fluorescence maps and micro-XANES spectra are presented.

The analysis of element distributions in polymer-based structures using IBA techniques offers the possibility to study a variety of interesting problems, in particular diffusion and reaction phenomena. Indium diffusion in model polymer light emitting diodes (p-LEDs) consisting of a stack Al/poly-(phenylenevinylene)/indium-tin-oxide/glass has been studied with Rutherford backscattering spectrometry (RBS), particle induced X-ray emission (PIXE), X-ray photoelectron spectroscopy (XPS), and low energy ion scattering (LEIS). A second example is provided by the analysis of organic optical gratings, in which the diffusion of labeled monomers during holographic photo-polymerization of photo-reactive monomer mixtures has been studied with μPIXE using a scanning proton microprobe. Since polymers are sensitive to ion irradiation, a new RBS/ERDA set-up has been constructed that is equipped with a sample holder mounted on a closed cycle helium refrigerator, which enables the cooling of samples to cryogenic temperature...