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International audience; The x-ray atomic properties of nickel (Ni) were investigated in a unique approach combining different experimental techniques to obtain new, useful and reliable values of atomic fundamental parameters for x-ray spectrometric purposes and for comparison with theoretical predictions. We determined the mass attenuation coefficients in an energy range covering the L-and K-absorption edges, the K-shell fluorescence yield and the $K\beta$ / $K\alpha$ and $K\beta_{1,3}$/$K\alpha_{1,2}$ transition probability ratios. The obtained line profiles and linewidths of the $K\alpha$ and $K\beta$ transitions in Ni can be considered as the contribution of the satellite lines arising from the [KM] shake processes suggested by Deutsch et al (1995 Phys. Rev. A 51 283) and Ito et al (2016 Phys. Rev. A 94 042506). Comparison of the new data with several databases showed good agreement, but also discrepancies were found with existing tabulated values.

The potential of valence to core Al X-ray emission spectroscopy to determine aluminum distribution in ferrierite zeolites was investigated. The recorded emission spectra of four samples prepared with different structure directing agents exhibit slight variations in the position of the main emission peak and the intensity of its low energy shoulder. Theoretical calculations indicate that an increased intensity of the Kβx shoulder in the Al emission spectra can be linked to a predominant occupation of the T3 site by a single aluminum atom. This study thus suggests that valence to core X-ray emission spectroscopy can be applied to help determine the occupation of aluminum at crystallographic T-sites in zeolites.

We report on vacuum ultraviolet (VUV) excited photoluminescence (PL) spectra emitted from a chemical vapor deposited MoS2 few-layered film. The excitation spectrum was recorded by monitoring intensities of PL spectra at ~1.9 eV. A strong wide excitation band peaking at 7 eV was found in the excitation. The PL excitation band is most intensive at liquid helium temperature and completely quenched at 100 K. Through first-principles calculations of photoabsorption in MoS2, the excitation was explicated and attributed to transitions of electrons from p- and d- type states in the valence band to the d- and p-type states in the conduction band. The obtained photon-in/photon-out results clarify the excitation and emission behavior of the low dimensional MoS2 when interacting with the VUV light sources.

In this work our previous study about chemical effects in the Kα spectra of S compounds employing high-resolution X-ray spectroscopy has been extended to the Kβ emission spectra. The measurements were performed with a wavelength dispersive single crystal spectrometer operated in the von Hamos geometry having an energy resolution comparable to the natural linewidth of the measured Kβ X-ray lines. The target fluorescence was produced by irradiating the samples with the bremsstrahlung from an X-ray tube. The energies and widths of the main components in the Kβ emission spectrum are given for different sulfur compounds (sulfide, sulfite, sulfate). The measured energy shifts between the Kβ lines of the compounds and elemental sulfur are presented as a function of the sulfur oxidation state and compared with the results obtained from the former Kα measurements.

The high-resolution von Hamos Bragg crystal spectrometer was constructed for the study of K X-ray emission from low- Z elements and L and M X-ray spectra of medium to high Z elements. Recently, this instrument was applied to high-resolution XES and RIXS studies using X-ray synchrotron radiation at the ID21 and BM5 beamlines at the ESRF. An outline of the spectrometer design and performance characteristics will be given. The studies deal with the energy dependent KL double photoexcitation of argon, the L 3 and M 1 atomic-level widths of elements 54≤ Z ≤77, and the evolution of the K-edge RIXS spectra of manganese oxides.

The high-resolution spectra of thorium Mα 1,2 (M 5 N 6,7 ) and Mβ(M 4 N 6 ) X-ray lines induced by O and Ne ions with energies 376 and 178 MeV, respectively, have been measured using a von Hamos crystal spectrometer. The measured spectra exhibit the pronounced X-ray satellite structure due to the multiple ionization in the N- and M-shells. In particular the N-shell satellites are well resolved and the M-shell hypersatellites are clearly observed, to the best of our knowledge, for the first time. The observed M-X-ray diagram transitions and their satellites are interpreted using the multi-configuration Dirac-Fock (MCDF) calculations performed for the multi-vacancy configurations including up to two spectator vacancies. The comparison shows that calculations for more vacancies are needed to reproduce the measured X-ray structure. On the other hand, the data are well interpreted qualitatively using a simplified model of the “average” MCDF satellites having binomially distributed intensities. Further MCDF calculations are in the progress, which ultimately allow to extract precise (∼0.5 eV) information on the electronic structure of the multiple ionized thorium.

The Kβ spectrum of 42Mo bombarded by 20.8 MeV/amu carbon ions was measured with high-resolution using a transmission-type bent crystal spectrometer operated in the modified DuMond slit geometry. The M-shell satellites of the Kβ2 transition could be well resolved, whereas for the Kβ1,3 transitions only a broadening and shift of the line centroid was observed. The composite structure of the satellite lines which consist of many components that vary in energy and strength was analyzed using theoretical energies and relative intensities obtained from multiconfiguration Dirac–Fock calculations. From the data analysis average M-shell satellite-to-diagram line yield ratios were deduced for both the Kβ1,3 and Kβ2 transitions. For the Kβ2 transition for which the relative contributions of the 3s,p and 3d spectator vacancies to the observed Kβ2M1 satellite yield could be determined, separated X(Kβ2M11,2,3):X(Kβ2M0) and X(Kβ2M14,5):X(Kβ2M0) yield ratios could even be extracted.

High-resolution measurements of the Kα x-ray spectra of metallic Ca, Ti, Cr and Fe were performed with a von Hamos Bragg crystal spectrometer. The target x-ray emission was induced by 34, 72 and 134 MeV C ions, 28, 64 and 230 MeV O ions and 43, 160 and 380 MeV Ne ions. The energies of the resolved KαLN x-ray satellite lines were determined. The possible variation of the energy differences between neighboring KαLN lines with the projectile energy, projectile atomic number and number of target L shell spectator vacancies was probed. No significant dependence on the projectile characteristics was observed. In contrast, the absolute energies of the KαLN satellite lines were found to depend on the projectile velocity. This dependence was attributed to the additional M shell ionization of the target atoms. Copyright © 2003 John Wiley & Sons, Ltd.

In this work two synchrotron radiation-based depth-sensitive X-ray fluorescence techniques, grazing incidence X-ray fluorescence (GIXRF) and grazing emission X-ray fluorescence (GEXRF), are compared and their potential for non-destructive depth-profiling applications is investigated. The depth-profiling capabilities of the two methods are illustrated for five aluminum-implanted silicon wafers all having the same implantation dose of 1016 atoms per cm2 but with different implantation energies ranging from 1 keV up to 50 keV. The work was motivated by the ongoing downscaling effort of the microelectronics industry and the resulting need for more sensitive methods for the impurity and dopant depth-profile control. The principles of GIXRF and GEXRF, both based on the refraction of X-rays at the sample surface to enhance the surface-to-bulk ratio of the detected fluorescence signal, are explained. The complementary experimental setups employed at the Physikalisch-Technische Bundesanstalt (PTB) for GIXRF and the University of Fribourg for GEXRF are presented in detail. In particular, for each technique it is shown how the dopant depth profile can be derived from the angular intensity dependence of the Al Kα fluorescence line. The results are compared to theoretical predictions and, for two samples, crosschecked with values obtained from secondary ion mass spectroscopy (SIMS) measurements. A good agreement between the different approaches is found proving that the GIXRF and GEXRF methods can be efficiently employed to extract the dopant depth distribution of ion-implanted samples with good accuracy and over a wide range of implantation energies.

X-ray and UV photons were used to store xenon atoms in polymeric films. The trapping was found to be stable at room temperature for Kapton and PVDC films. In Kapton, concentrations of xenon up to about 18.5 mg/cm3 were attained. The dependence of the rare gas concentration on the irradiation dose, film thickness, gas pressure, and on the polymers and gases nature was probed. The results are interpreted in terms of a simple three-step model: the xenon atoms are first physisorbed at the surface of the substrate and then diffuse into the bulk where they are finally trapped as a result of radiation chemistry effects of the UV or X-rays on the structure of the polymer.

We report on the study of heavy-ion-induced Si KL x-ray satellite spectra of several 3d, 4d and 5d silicides, with the aim of elucidating the trends in bonding properties of transition metal (TM) silicides. Measurements of the 43 MeV Ne3+-beam-induced Si KL spectra of elemental silicon and compound targets were performed at the Paul Scherrer Institute, Villigen, Switzerland, with a high-resolution von Hamos crystal spectrometer. The interpretation of the data was based on the importance of the effect of the solid and chemical environment on the KL x-ray satellite relative intensities due to the L-vacancy refilling by intra- and inter-atomic electron transitions. Within the framework of a statistical procedure for L-shell vacancy refilling the average L-shell rearrangement probability for each silicide was extracted so that calculated x-ray intensity distributions matched the experimental ones. The results are discussed in terms of the interplay of Si-Si, Si-TM and TM-TM bonding interactions in the studied TM silicides.

High-resolution measurements of the Kα 1,2 X-ray spectra were performed with a bent crystal diffraction spectrometer for zirconium, niobium, molybdenum and palladium targets bombarded by 280 and 360 MeV oxygen ions. The energy differences between the Kα 1,2 diagram and the K h α 1,2 hypersatellite transitions as well as the intensity ratios I ( K h α 1 )/ I ( K h α 2 ) were determined. The L-shell satellites of the diagram and of the hypersatellite lines were resolved. The data are interpreted in terms of the properties of He-like hole states in mid- Z atoms. The Breit interaction correction is determined. The corrections due to the unresolved M-shell satellites and to the QED are found to be much smaller than the Breit terms and comparable to the experimental accuracy.

A new technique which allows the storage of noble gases in polymeric films at ambient temperature was successfully developed. The trapping of the rare gases in the polymer takes place via X-ray irradiation of the gas and the polymer film by means of an X-ray tube. Concentrations up to about 2 × 1017 atoms of noble gas per cm2 of the film were obtained. The thermal energy needed for desorbing Xe from a kapton film was found to be about 16 kcal/mol which is large compared with the known values for thermal desorptions on metal surfaces. An energy shift of 1.04 ± 0.48 eV was further observed for the 5p–1s X-ray transition of trapped Xe atoms, which permits to surmise a rather strong interaction between the sorbate atoms and the sorbent molecules. Two interpretations of the observed phenomena are presented, the first involves bond ruptures and bond rearrangements in the polymer whereas the second is based on the assumption that chemisorption or persorption of Xe occurs in the polymeric substrate.

The K–LM radiative Auger (RA) x-ray spectrum of argon was observed. The transitions were photoinduced by means of an x-ray tube and measured with two different high-resolution curved crystal spectrometers of reflection-type geometry. From the first measurements performed at the Paul Scherrer Institute (PSI), only an upper limit of 0.25% relatively to the intensity of the Kα1,2 diagram line could be obtained for the total K—LM RA yield. From a second experiment carried out at the University of Fribourg, a I(K–LM RA)/I(Kα1,2) ratio of 0.18±0.05% was obtained. This value is consistent with the PSI result but in strong disagreement with theoretical predictions based on the shake model, which are about four times larger. © 1998 John Wiley & Sons, Ltd.

The photoinduced $K\ensuremath{\alpha}$ and $K\ensuremath{\beta}$ x-ray spectra of argon and krypton were measured by means of high-resolution crystal diffractometry. Ar $K{\ensuremath{\alpha}}_{1,2}{L}^{(1)}$ and $K{\ensuremath{\beta}}_{1,3}{M}^{(1,2)}$ and Kr $K{\ensuremath{\alpha}}_{1}{L}^{(1)}$ and $K{\ensuremath{\beta}}_{2}{M}^{(1,2)}$ satellites were observed and resolved from the corresponding diagram lines. From the satellite to parent diagram line yield ratios, the probabilities for producing via shake processes ${K}^{(1)}{L}^{(1)}$ and ${K}^{(1)}{M}^{(1)}$ double-hole states were deduced. The results are compared to the few other existing experimental data and to theoretical sudden approximation predictions. The latter are found to underestimate somewhat the experimental values.

The mechanisms leading to the production of hollow K shell atoms via single photon impact were investigated for a variety of light elements with 12 ≤ Z ≤ 23. The double 1s vacancy states were produced by irradiating the samples with intense monoenergetic synchrotron radiation beams. The double-to-single K-shell photoionization probabilities PKK and the absolute double K-shell photoionization cross sections σ²⁺ were determined by measuring with a high-resolution bent von Hamos crystal spectrometer the Kαh hypersatellite X-ray emission of the samples. The measurements were performed over a wide range of incoming photon energies from threshold up to energies beyond the broad maximum of the double-to-single photoionization cross section ratios. The PKK and σ²⁺ were determined from the relative yields of the resolved Kαh hypersatellite lines. For Mg, Al and Si, the two-electron one-photon (TEOP) Kααh transitions which represent an alternative but much weaker decay channel for double 1s vacancy states could be also observed, using a highly efficient flat crystal wavelength dispersive spectrometer. This observation of single photon-induced TEOP transitions has shown that the I(Kαh)/I(Kααh) branching ratios are very poorly reproduced by most of existing theoretical models. Besides the relative yields of the hypersatellite and TEOP transitions, the energies and natural linewidths of the Kαh and Kααh X-ray lines were also determined. The energies are found to be in good agreement with different theoretical predictions, whereas the linewidths are significantly underestimated by the calculations, except if non-lifetime broadening effects such as the outer-shell ionization and the open valence configuration are taken into consideration.

The first experimental results of a high-resolution study of Th and U Lγ-X-rays induced in collisions with 230 MeV and 360 MeV oxygen ions, undertaken to investigate the dynamics of the multiple ionization in M-, N- and O-shells and the structure of M- and N-shell X-ray satellites, are reported. The measurements were performed using the transmission curved- crystal spectrometer installed in DuMond geometry. An instrumental resolution of about 10 eV was achieved for Lγ (L-N,O) X-ray transitions, allowing clear separation of M-shell X-ray satellites for Th and U. Moreover, the N-shell satellite structure in the Lγ6 (L2-O4) X-ray transition was observed for 360-MeV O ion impact on a thorium target. This, to our knowledge, is the first observation of this kind. Other observed Lγ X-ray diagram lines are shifted and widened, with respect to the photoinduced X-ray spectra excited by an X-ray tube, due to the unresolved N-shell and, probable the O-shell, satellite structure.

An observation of the internal structure of the L-shell hypersatellite x rays resulting from the one-photon decay of L{sup -2} double-vacancy states in palladium multiply ionized by oxygen ions is reported. The Pd L{sub 3}{yields}M{sub 4,5} x-ray spectrum was measured with a von Hamos high-resolution crystal spectrometer. The complex shape of the observed spectrum could be interpreted in detail using relativistic multiconfiguration Dirac-Fock calculations. The relative intensities of the measured x rays were found to be in good agreement with semiclassical approximation calculations using relativistic Dirac-Hartree-Fock wave functions.

A diffraction spectrometer with a quartz crystal bent to the radius of 4.64 m has been installed at the beam line of KVI variable energy cyclotron. The instrument is intended for a detailed study of KX-rays from multiply ionized atoms with Z > 56. The KX-ray spectra of Tb bombarded with 15 MeV/amu 4He and 20Ne ions are presented along with the calibration 84.257 keV gamma line of 170Yb. The L-shell ionization probabilities in near central collisions are deduced from the measured L-satellite yield distribution.

We demonstrate that ultralow-level Al impurities on a silicon surface can be measured by using the high-resolution grazing emission x-ray fluorescence (GEXRF) technique combined with synchrotron-radiation excitation. An Al-impurity level of about ${10}^{12}\text{ }\text{atoms}/{\text{cm}}^{2}$ was reached by observing the $\text{Al}\text{ }K\ensuremath{\alpha}$ x-ray fluorescence in the resonant Raman-scattering background-``free'' regime by choosing an appropriate beam energy below the $\text{Si}\text{ }K$ absorption edge. Present results show that by combining the GEXRF method with the vapor phase decomposition technique the ${10}^{7}\text{ }\text{atoms}/{\text{cm}}^{2}$ level can be reached for Al detection on silicon. Finally, we found that the high-resolution GEXRF technique is a sensitive tool to study the morphology of surface nanostructures.

The Kβ X-ray spectrum of molybdenum bombarded by 28 MeV 4He ions was measured with a transmission curved crystal spectrometer. L and even M satellite lines were observed and resolved. Experimental energies are compared with those calculated with a MCDF program. Satisfactory agreement is found. Measuring the Kβ X-ray spectra with high resolution is a novel technique to also determine the M-shell ionization probability in central collisions. Comparison of the value obtained for Mo with theoretical (SCA) predictions demonstrates the importance of the recoil term.

We demonstrate that in order to interpret the x-ray satellite structure of Pd Lα1,2(L₃M4,5) transitions excited by fast O ions, which was measured using a high-resolution von Hamos crystal spectrometer, the vacancy rearrangement processes, taking place prior to the x-ray emission, have to be taken into account. The measured spectra were compared with the predictions of the multi- con.guration Dirac-Fock (MCDF) calculations using the fluorescence and Coster- Kronig yields which were modiffed due to a reduced number of electrons available for relaxation processes and the effect of closing the Coster-Kronig transitions. We demonstrate that the vacancy rearrangement processes can be described in terms of the rearrangement factor, which can be calculated by solving the system of rate equations modelling the flow of vacancies in the multiply ionized atom. By using this factor, the ionization probability at the moment of collision can be extracted from the measured intensity distribution of x-ray satellites. The present results support the independent electron picture of multiple ionization and indicate the importance of use of Dirac-Hartree-Fock wave functions to calculate the ionization probabilities.

X-ray resonant Raman scattering (RRS) spectra of Al, Al{sub 2}O{sub 3}, Si, and SiO{sub 2} were measured at the European Synchrotron Radiation Facility, using a high-resolution Bragg-type curved crystal spectrometer. The x-ray RRS spectra were collected at several beam energies tuned below the 1s absorption thresholds of Al and Si. Differences in the spectral features between the elemental samples and the oxide ones were clearly observed. The data were interpreted using the second-order perturbation theory within the Kramers-Heisenberg (KH) approach. It is shown that, using the KH formalism, oscillator strengths that are similar to the ones deduced from x-ray absorption measurements can be extracted from emission x-ray RRS spectra. The total cross sections for the x-ray RRS process were derived for the different photon beam energies and compared with theoretical predictions. For elemental silicon, the weak 1s-3p excitation was observed and found to be consistent with results of density of states calculations.

High energy resolution off-resonant X-ray emission spectroscopy (HEROS) was applied to study one-photon (OPA) and two-photon absorption (TPA) processes in metallic copper generated by ultra-short hard X- ray FEL pulses from the Linac Coherent Light Source (LCLS). The OPA and TPA signals were measured using a multiple-crystal von Hamos diffraction spectrometer allowing observation of both the intermediate and final states in the TPA process. The universal scaling of TPA/OPA cross sections is discussed.

We report on the first high-resolution measurements of the K x-ray resonant Raman scattering (RRS) in Si. The measured x-ray RRS spectra, interpreted using the Kramers-Heisenberg approach, revealed spectral features corresponding to electronic excitations to the conduction and valence bands in silicon. The total cross sections for the x-ray RRS at the 1s absorption edge and the 1s-3p excitation were derived. The Kramers-Heisenberg formalism was found to reproduce quite well the x-ray RRS spectra, which is of prime importance for applications of the total-reflection x-ray fluorescence technique.

K-X-ray spectra of Zr, Nb, Mo and Pd targets bombarded with 250 MeV carbon and 360 MeV oxygen ions are studied with high resolution diffraction spectrometry. Relative yields and natural widths of the Khα1,2 hypersatellite lines are determined and compared with those of the diagram lines. The widths of Khα1,2 lines are compared with the new phenomenological formula which takes into account the retardation of the Khα₁ transition in the LS coupling scheme. The data significantly exceed the expected values. Deduced lifetimes of the double K-hole states are shorter than expected.

The K{beta}{sub 2} x-ray spectra of zirconium, niobium, molybdenum, and palladium targets bombarded with 20.8-MeV/amu {sup 12}C ions were measured with a high-resolution transmission-type bent crystal spectrometer. Well resolved M{sup 1} and M{sup 2} satellite lines were observed. Average M-shell and 3s,p- and 3d-subshell ionization probabilities for nearly central collisions were deduced. These values are compared with theoretical predictions from the semiclassical approximation using hydrogenlike and Dirac-Hartree-Fock wave functions. The experimental energy shifts of the K{beta}{sub 2} M{sup m=1,2} satellite lines are compared with values obtained from extensive multiconfiguration Dirac-Fock calculations.

High-resolution measurements of the photoinduced ${L}_{3}\ensuremath{-}{M}_{1}$ and ${L}_{3}\ensuremath{-}{M}_{4,5}$ x-ray emission lines were performed with a reflection-type bent-crystal spectrometer for a variety of elements ranging from xenon $(Z=54)$ to iridium $(Z=77).$ The measurements were performed at the European Synchrotron Radiation Facility in Grenoble, France. From the observed linewidths of the ${L}_{3}\ensuremath{-}{M}_{1}$ x-ray transitions, the widths of the ${M}_{1}$ levels were determined using the ${L}_{3}$ level widths extracted from the measured ${L}_{3}\ensuremath{-}{M}_{5}$ transitions, and assuming for the ${M}_{5}$ levels the widths reported recently by Campbell and Papp [At. Data Nucl. Data Tables 77, 1 (2001)]. In the rare-earth region a Z-dependent broadening of the ${M}_{1}$ level was observed.

High‐resolution measurements of the K x‐ray spectra of metallic Ca, Ti, Cr, and Fe were performed with a von Hamos Bragg crystal spectrometer. The target x‐ray emission was induced by by 2–19 MeV/amu C, O and Ne ions. The energies of the well resolved KαLN X‐ray satellite lines were determined. Based on the measured values the empirical formula for the KαLN satellite energy shift of the 3d transition elements is given. For the Ca and Ti target bombarded with C ions also the KαhLN hypersatellite lines the KβLN satellite lines and even the KβhLN hypersatellite lines have been measured and their energies determined. The possible variation of the energy differences between neighboring satellite and hypersatellite lines with the projectile energy and atomic number was probed. No significant dependence on the projectile characteristics was observed. In contrast to that the absolute energies of the satellite and hypersatellite lines lines were found to depend on the projectile velocity. This dependence was attri...

High‐resolution measurements of the L1‐M4,5 fluorescence x‐ray lines of Sm, Ho, Yb, W, Pt, Hg and Bi were performed, using a transmission DuMond‐type and a reflection von Hamos‐type bent crystal spectrometer. Despite the poor intensity of the dipole‐forbidden transitions, precise linewidths were obtained. Assuming for the M4,5 level widths the values reported recently by Campbell and Papp, the L1 level widths of the investigated elements could be determined with a precision of 4–10%. A good agreement with Campbell and Papp’s data was observed for the heaviest elements. For Sm and Ho, however, an intriguing discrepancy was found. The latter was explained by a splitting effect of the L1 subshell resulting from the coupling of the 2s electron spin in the initial excited state with the total spin of the open 4f level. Based on this splitting picture, adjustements of the L1 level widths recommended by Campbell and Papp were proposed for the lanthanides region.

The fluorescence $\mathrm{KL}$ x-ray emission of argon induced by impact with monoenergetic photons was observed with a high-resolution reflecting-type bent crystal spectrometer. The measurements were performed at the European Synchrotron Radiation Facility in Grenoble, France. X-ray beam energies in the range $3455 \mathrm{eV}l~\ensuremath{\Elzxh}\ensuremath{\omega}l~6540 \mathrm{eV}$ were used to investigate the $K+L$ double excitation from threshold to saturation. The excitation probabilities were deduced from the satellite-to-diagram line yield ratios $\mathrm{I}(KL\ensuremath{-}{L}_{2,3}L): \mathrm{I}(K\ensuremath{-}{L}_{2,3}).$ Results were compared to predictions based on the model of Thomas and the one of Roy. From the comparison, parameters such as excitation onset energies, high-energy limit shake probabilities, and radius of the $2p$ orbital in ionic Ar were deduced. The satellite line shapes and their evolution with the excitation energy were analyzed with the aid of multiconfiguration Dirac-Fock calculations.

The Kα hypersatellite X-ray spectrum of 42Mo target bombarded with 17 MeV/u 16O ions was measured with a high-resolution transmission bent crystal spectrometer. Well resolved lines of L-satellites and K-hypersatellites of Kα1 and Kα2 transitions were observed. Such data give valuable and rich information for testing the approximation used for the description of the multielectron system. The Khα1 hypersatellite, treated as spin-flip 1S0→3P1 transition, is forbidden in pure L-S coupling. In that case the relative yields of the Kα hypersatellites reflect directly the degree of intermediate coupling in the atom. Moreover, energies of the Khα1.2L0,1 transitions and the I(Khα1L0,1)/I(Khα2L0,1) intensity ratios are much more influenced by the Breit interaction than the diagram lines. The discussion of these problems is illustrated with the measured Kα hypersatellite spectrum of 42Mo.

We report on the application of synchrotron radiation based high-resolution grazing-emission x-ray fluorescence (GEXRF) method to measure low-level impurities on silicon wafers. The presented high-resolution GEXRF technique leads to direct detection limits of about 10¹² atoms/cm². The latter can be presumably further improved down to 10⁷ atoms/cm² by combining the synchrotron radiation-based GEXRF method with the vapor phase decomposition preconcentration technique. The capability of the high-resolution GEXRF method to perform surface-sensitive elemental mappings with a lateral resolution of several tens of micrometers was probed.

An in-beam curved crystal spectrometer facility has been installed at the SIN variable energy cyclotron. The radius of curvature is 3.15 m. Using the (110) planes of different bent quartz laminas, diffraction peaks down to Δθ = 5 arcsec FWHM are obtained. The energy resolution is thus ΔE ⋍ 0.01 E 2 /n , where n is the diffraction order, ΔE being expressed in eV and E in keV. The spectrometer has been constructed to cover an angular range of ±10°. Transitions in the range 17 to about 350 keV have so far been observed. Measurements have been performed in conventional line source DuMond geometry and in slit geometry. The instrument is being used for the high-resolution observation of X- and gamma-rays induced by proton, helium- and oxygen-ion bombardment.

Various 3-dimensional nano-scaled periodic structures with different configurations and periods deposited on the surface of silicon and silica substrates were investigated by means of the grazing incidence and grazing emission X-ray fluorescence techniques. Apart from the characteristics which are typical for particle- and layer-like samples, the measured angular intensity profiles show additional periodicity-related features. The latter could be explained by a novel theoretical approach based on simple geometrical optics (GO) considerations. The new GO-based calculations were found to yield results in good agreement with experiment, also in cases where other theoretical approaches are not valid, e.g., periodic particle distributions with an increased surface coverage. (C) 2014 Elsevier B.V. All rights reserved.