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For scanning x-ray microscopy, many attempts have been made to image the phase contrast based on a concept of the beam being deflected by a specimen, the so-called differential phase contrast imaging (DPC). Despite the successful demonstration in a number of representative cases at moderate spatial resolutions, these methods suffer from various limitations that preclude applications of DPC for ultra-high spatial resolution imaging, where the emerging wave field from the focusing optic tends to be significantly more complicated. In this work, we propose a highly robust and generic approach based on a Fourier-shift fitting process and demonstrate quantitative phase imaging of a solid oxide fuel cell (SOFC) anode by multilayer Laue lenses (MLLs). The high sensitivity of the phase to structural and compositional variations makes our technique extremely powerful in correlating the electrode performance with its buried nanoscale interfacial structures that may be invisible to the absorption and fluorescence contrasts.

We have implemented a coherent x-ray diffraction imaging technique that scans a phase plate to modulate wave-fronts of the x-ray beam transmitted by samples. The method was applied to measure a decorative alkyd paint containing iron oxide red pigment particles. By employing an iterative algorithm for wave-front modulation phase retrieval, we obtained an image of the paint sample that shows the distribution of the pigment particles and is consistent with the result obtained from a transmission x-ray microscope. The technique has been experimentally proven to be a feasible coherent x-ray imaging method with about 120 nm spatial resolution and was shown to work well with industrially relevant specimens. [ABSTRACT FROM AUTHOR]

Abstract: We report high-resolution X-ray diffraction studies of combinatorial epitaxial Ge (001) thin-films with varying doping concentrations of Co and Mn grown on Ge (001) substrates. The crystalline structure of the epitaxial thin-film has been determined using crystal-truncation rod (CTR) measurements and fitting analysis. By analyzing the fine interference fringes in the CTR intensity profile, strain sensitivity of ∼0.003% has been achieved. Using this method, the evolution of interfacial structures has been quantified as a function of doping concentration. [Copyright &y& Elsevier]

The authors report a study of structural and chemical disorders in a ternary combinatorial epitaxial film of CoxMnyGe1-x-y in the composition range that includes the Heusler alloy Co2MnGe, using microbeam anomalous x-ray diffraction techniques. The structural and chemical ordering of the alloy has been found to be extremely stable over a large composition range, while elemental site swapping and sublattice vacancies have been identified. A model of anomalous diffraction around the Co and Ge edges is presented and shown to make possible the identification and quantification of these disorders in an epitaxial film. [ABSTRACT FROM AUTHOR]

We describe a high-throughput scanning X-ray fluorescence (XRF) microscopy setup using a microfocused synchrotron X-ray beam, which is optimized for in-parallel X-ray characterization of composition and crystalline structure of combinatorial samples. We present X-ray fluorescence elemental maps of a full ternary CoxMnyGe1−x−y composition-spread thin film and discuss the quantitative analysis method used for obtaining the ternary composition. [Copyright &y& Elsevier]

We discuss important experimental considerations and high-throughput synchrotron-based techniques for structural characterization of binary and ternary composition-spread thin films. We apply these techniques to obtain detailed structural phase diagrams of CoMnGe ternary alloy system. [Copyright &y& Elsevier]

Abstract: In conventional bulk alloy phase diagrams, each discrete composition point is prepared and characterized one at a time, and consequently has a different thermodynamic history. The continuous phase diagram (CPD) offers a unique opportunity to conduct high throughput construction of thin film phase diagram with single universal thermodynamic history applied to all the compositions. Here, we performed the CPD experiment of Fe–Ni–Co ternary alloy system using combinatorial ion beam sputtering system. The high throughput screenings of structural and physical properties were made using scanning microbeam X-ray diffractometer, scanning magneto-optic Kerr effect (SMOKE) measurement, and scanning nano-indentation microscope. The results are consistent with the known structural phases and phase boundaries. In addition, we identified two very narrow amorphous regions, carefully examined and confirmed by synchrotron microbeam X-ray diffraction studies. [Copyright &y& Elsevier]