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Quantitative characterization of local strain in silicon wafers is critical in view of issues such as wafer handling during manufacturing and strain engineering. In this work, full-field X-ray microdiffraction imaging using synchrotron radiation is employed to investigate the long-range distribution of strain fields in silicon wafers induced by indents under different conditions in order to simulate wafer fabrication damage. The technique provides a detailed quantitative mapping of strain and defect characterization at the micrometer spatial resolution and holds some advantages over conventional methods. [ABSTRACT FROM AUTHOR]

While channel-cut crystals, in which the diffracting surfaces in an asymmetric cut are kept parallel, can provide beam collimation and spectral beam shaping, they can in addition provide beam compression or expansion if the cut is V-shaped. The compression/expansion ratio depends in this case on the total asymmetry factor. If the Ge(220) diffraction planes and a total asymmetry factor in excess of 10 are used, the rocking curves of two diffractors will have a sufficient overlap only if the second diffractor is tuned slightly with respect to the first one. This study compares and analyses several ways of overcoming this mismatch, which is due to refraction, when the Cu Kα1 beam is compressed 21-fold in a V21 monochromator. A more than sixfold intensity increase was obtained if the matching was improved either by a compositional variation or by a thermal deformation. This provided an intensity gain compared with the use of a simple slit in a symmetrical channel-cut monochromator. The first attempt to overcome the mismatch by introducing different types of X-ray prisms for the required beam deflection is described as well. The performance of the V-shaped monochromators is demonstrated in two applications. A narrow collimated monochromatic beam obtained in the beam compressing mode was used for high-resolution grazing-incidence small-angle X-ray scattering measurements of a silicon sample with corrupted surface. In addition, a two-dimensional Bragg magnifier, based on two crossed V15 channel monochromators in beam expansion mode and tuned by means of unequal asymmetries, was successfully applied to high-resolution imaging of test structures in combination with a Medipix detector. [ABSTRACT FROM AUTHOR]

The white beam (∼6–80 keV) available at the TopoTomo X-ray beamline of the ANKA synchrotron facility (KIT, Karlsruhe, Germany) was used to perform edge-enhancement imaging tests on lithium fluoride radiation detectors. The diffracted X-ray image of a microscopic boron fibre, consisting of tungsten wire wrapped by boron cladding, was projected onto lithium fluoride thin films placed at several distances, from contact to 1 m . X-ray photons cause the local formation of primary and aggregate colour centres in lithium fluoride; these latter, once illuminated under blue light, luminesce forming visible-light patterns—acquired by a confocal laser scanning microscope—that reproduce the intensity of the X-ray diffracted images. The tests demonstrated the excellent performances of lithium fluoride films as radiation detectors at the investigated photon energies. The experimental results are here discussed and compared with those calculated with a model that takes into account all the processes that concern image formation, storing and readout. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a group of Lu2SiO5:Tb (LSO:Tb) scintillating layers with a Tb concentration between 8% and 19% were investigated by means of synchrotron and laboratory techniques. The scintillation efficiency measurements proved that the highest light yield is obtained for a Tb concentration equal to 15%. At higher concentration, quenching processes occur which lower the light emission. The analysis of the reciprocal space maps of the (082) (280) and (040) Bragg reflections showed that LSO:Tb epilayers are well adapted on YbSO substrates for all the investigated concentrations. The spatial resolution tests demonstrated the possibility to achieve a resolution of 1 μm with a 6 μm thick scintillating layer. [Copyright &y& Elsevier]

Abstract: In this work, we present preliminary in-line X-ray lensless projection imaging results at a synchrotron facility by using novel solid-state detectors based on non-destructive readout of photoluminescent colour centres in lithium fluoride thin films. The peculiarities of LiF radiation detectors are high spatial resolution on a large field of view, wide dynamic range, versatility and simplicity of use. These properties offered the opportunity to test a broadband X-ray synchrotron source for lensless projection imaging experiments at the TopoTomo beamline of the ANKA synchrotron facility by using a white beam spectrum (3–40 keV). Edge-enhancement effects were observed for the first time on a test object; they are discussed and compared with simulations, on the basis of the colour centre photoluminescence linear response found in the investigated irradiation conditions. [Copyright &y& Elsevier]

Abstract: Novel X-ray imaging detectors based on photoluminescence of colour centres in lithium fluoride (LiF) have been proposed and tested for extreme ultraviolet, soft and hard X-rays up to 10keV. For the first time we present the optical characterisation of LiF crystals and thin films irradiated at the TOPO–TOMO beamline of synchroton light source Anka (Karlsruhe, Germany) in the energy range 6–40keV for different exposure times. Absorption and photoluminescence spectra were analysed to study the optical response of the LiF-based detectors. High resolved X-ray imaging of commercial test patterns has been obtained on LiF crystals and films by optical readout with a confocal laser scanning fluorescence microscope. [Copyright &y& Elsevier]

Abstract: Synchrotron-radiation imaging was applied to the non-destructive testing of detector devices during their development cycle. Transmission imaging known as computed laminography was used to examine the microstructure of the interconnections in order to investigate the perfection of technological steps necessary for hybrid detector production. A characterisation of the solder bump microstructure can reveal production flaws such as missing or misaligned bumps, voids in bumps or bridges and thus give valuable information about the bonding process. [Copyright &y& Elsevier]

Abstract: Hybrid pixel detectors, with the X-ray conversion layer and the readout electronics realised in two separate semiconducting crystals, offer the unique possibility to observe effects of dynamical diffraction directly in a crystal sensor. The sensor can be used to Bragg diffract X-rays in transmission geometry and simultaneously to observe the wave fields generated inside the sensor through absorption thus producing signals in the pixel readout. A monochromatic beam of sufficiently high energy is used to obtain a large absorption length inside the sample. This allows to use a setup geometry with the narrow incident beam hitting from the side of the platelet-shaped sensor, parallel to the readout electronics, so that the whole Borrmann triangle can be observed inside the sample. We used a Medipix2 detector with a silicon sensor layer to observe diffraction in both transmission and reflection geometry. [Copyright &y& Elsevier]

Abstract: Within the project ScinTAX of the 6th framework program (FP6) of the European Commission (SCINTAX—STRP 033 427) we have developed a new thin single crystal scintillator for high-resolution X-ray imaging. The scintillator is based on a Tb-doped Lu2SiO5 (LSO) film epitaxially grown on an adapted substrate. The high density, effective atomic number and light yield of the scintillating LSO significantly improves the efficiency of the X-ray imaging detectors currently used in synchrotron micro-imaging applications. In this work we present the characterization of the scintillating LSO films in terms of their spatial resolution performance and we provide two examples of high spatial and high temporal resolution applications. [Copyright &y& Elsevier]

Abstract: One of the most promising methods of phase-contrast imaging is the Talbot grating interferometry. We report about the optimization of the method for fast imaging, requiring reduced exposure times by keeping sufficient imaging contrast. To do this a new Talbot interferometer working with a broad energy bandwidth beam has been installed at the Topo–Tomo beamline at ANKA. We demonstrate the method with a filtered white beam and without the need of a source grating that is commonly used at moderate-emittance synchrotron sources. Taking advantage of a higher photon flux, the exposure time is significantly reduced. At the same time, images obtained with this setup show a sufficient visibility contrast of 25% on average, which opens the way for new applications in real-time measurements. [Copyright &y& Elsevier]