Showing papers on "Synchrotron radiation published in 2004"
TL;DR: It is demonstrated that a beam of x-ray radiation can be generated by simply focusing a single high-intensity laser pulse into a gas jet, which has keV energy and lies within a narrow cone angle.
Abstract: We demonstrate that a beam of x-ray radiation can be generated by simply focusing a single high-intensity laser pulse into a gas jet. A millimeter-scale laser-produced plasma creates, accelerates, and wiggles an ultrashort and relativistic electron bunch. As they propagate in the ion channel produced in the wake of the laser pulse, the accelerated electrons undergo betatron oscillations, generating a femtosecond pulse of synchrotron radiation, which has keV energy and lies within a narrow (50 mrad) cone angle.
590 citations
TL;DR: In this paper, the authors used a 6 μm diameter liquid-jet free vacuum surface at the MBI undulator beamline of the synchrotron radiation facility BESSY to study the valence band photoelectron spectra of liquid water.
Abstract: The valence band photoelectron spectra of liquid water (H2O and D2O) are studied in the photon energy range from hν = 60 to 120 eV. The experiments use a 6 μm diameter liquid-jet free vacuum surface at the MBI undulator beamline of the synchrotron radiation facility BESSY. Photoelectron emission from all four valence molecular orbitals (MOs) is observed. In comparison to those of the gas phase, the peaks are significantly broadened and shifted to lower binding energies by about 1.5 eV. This is attributed primarily to the electronic polarization of the solvent molecules around an ionized water molecule. Energy shifts, peak broadening, and relative peak intensities for the four MOs differ because of their specific participation in the hydrogen bonding in liquid water. Relative photoionization cross sections for MOs were measured for hν = 60, 80, and 100 eV. The main difference for liquid water, as compared to the gas phase, is the relative intensity decrease of the 1b2 and 3a1 orbitals, reflecting changes o...
359 citations
TL;DR: The systematic exploitation of anisotropic thermal expansion will help reduce the effects of peak overlap in the analysis of powder diffraction data.
Abstract: The optical design and performance of the high-resolution powder diffraction beam line BM16 at ESRF are discussed and illustrated. Some recent studies carried out on BM16 are described, including crystal structure solution and refinement, anomalous scattering, in situ measurements, residual strain in engineering components, investigation of microstructure, and grazing-incidence diffraction from surface layers. The beam line is built on a bending magnet, and operates in the energy range from 5 keV to 40 keV. After the move to an undulator source in 2002, it will benefit from an extented energy range up to 60 keV and increased flux and resolution. It is anticipated that enhancements to the data quality will be achieved, leading to the solution of larger crystal structures, and improvements in the accuracy of refined structures. The systematic exploitation of anisotropic thermal expansion will help reduce the effects of peak overlap in the analysis of powder diffraction data.
239 citations
TL;DR: Nuclear resonant scattering with synchrotron radiation (SR) is introduced on a basic level in this paper, where the theoretical background and experimental aspects of two popular methods with a widening range of applications are discussed.
Abstract: Nuclear resonant scattering techniques with synchrotron radiation (SR) are introduced on a basic level. We focus on the theoretical background and on experimental aspects of two popular methods with a widening range of applications, nuclear resonant inelastic x-ray scattering and synchrotron Mossbauer spectroscopy. The inelastic method provides specific vibrational information, e.g., the phonon density of states. The Mossbauer method permits determination of hyperfine interactions. All nuclear resonance techniques take full advantage of the unique properties of SR: intensity, collimation, time structure, and polarization. As a result both methods discussed here have led to novel applications for materials under extreme conditions, proteins with biological functionality, and magnetic nanostructures.
198 citations
TL;DR: In this article, the use of electron spectroscopies to characterize self-assembled monolayers (SAMs) is discussed, focusing on thiol-derived monolayer on gold with emphasis on n-alkanethiols.
197 citations
Book•
01 Jan 2004
TL;DR: In this paper, the underlying physics of synchrotron radiation and its main properties are explained and applications are investigated, including electron storage rings as radiation sources and the effect of the emitted radiation on the electron beam.
Abstract: This book explains the underlying physics of synchrotron radiation and derives its main properties. It is divided into four parts. The first covers the general case of the electromagnetic fields created by an accelerated relativistic charge. The second part concentrates on the radiation emitted by a charge moving on a circular trajectory. The third looks at undulator radiation, covering plane weak undulators, strong undulators and other more general undulators. The final part deals with applications and investigates the optics of synchrotron radiation dominated by diffraction due to the small opening angle. It also includes a description of electron storage rings as radiation sources and the effect of the emitted radiation on the electron beam. This book provides a valuable reference for scientists and engineers in the field of accelerators, and all users of synchrotron radiation.
197 citations
Book•
01 Jan 2004
TL;DR: In this paper, the effect of Insertion Devices on the Electron Beam has been discussed, and a number of novel and exotic insertion devices for free electron Lasers have been proposed.
Abstract: 1. Introduction 2. Fundamentals of Synchrotron Radiation Emission 3. Synchrotron Radiation Output from Multipole Wigglers 4. Synchrotron Radiation Output from Undulators 5. Computation of Synchrotron Radiation 6. Generation of Polarized Light 7. Permanent Magnet Based Design of Insertion Devices 8. Electromagnet Based Design of Insertion Devices 9. Measurement and Correction of Insertion Devices 10. The Effect of Insertion Devices on the Electron Beam 11. Insertion Devices for Free Electron Lasers 12. Novel and Exotic Insertion Devices References
172 citations
TL;DR: In this paper, a high-resolution phase contrast imaging technique has been used for the reconstruction of clear crack images together with the details of microstructural features, and its feasibility is confirmed.
172 citations
Book•
01 Jan 2004
TL;DR: The role of X-ray Spectrometry in Chemical Analysis and Outlining the Volume is discussed in this paper, where the authors consider the role of x-ray spectrometers in chemical analysis.
Abstract: Contributors.Preface.1 Introduction.1.1 Considering the Role of X-ray Spectrometry in Chemical Analysis and Outlining the Volume.2 X-Ray Sources.2.1 Micro X-ray Sources.2.2 New Synchrotron Radiation Sources.2.3 Laser-driven X-ray Sources.3 X-Ray Optics.3.1 Multilayers for Soft and Hard X-rays.3.2 Single Capillaries X-ray Optics.3.3 Polycapillary X-ray Optics.3.4 Parabolic Compound Refractive X-ray Lenses.4 X-Ray Detectors.4.1 Semiconductor Detectors for (Imaging) X-ray Spectroscopy.4.2 Gas Proportional Scintillation Counters for X-ray Spectrometry.4.3 Superconducting Tunnel Junctions.4.4 Cryogenic Microcalorimeters.4.5 Position Sensitive Semiconductor Strip Detectors.5 Special Configurations.5.1 Grazing-incidence X-ray Spectrometry.5.2 Grazing-exit X-ray Spectrometry.5.3 Portable Equipment for X-ray Fluorescence Analysis.5.4 Synchrotron Radiation for Microscopic X-ray Fluorescence Analysis.5.5 High-energy X-ray Fluorescence.5.6 Low-energy Electron Probe Microanalysis and Scanning Electron Microscopy.5.7 Energy Dispersive X-ray Microanalysis in Scanning and Conventional Transmission Electron Microscopy.5.8 X-Ray Absorption Techniques.6 New Computerisation Methods.6.1 Monte Carlo Simulation for X-ray Fluorescence Spectroscopy.6.2 Spectrum Evaluation.7 New Applications.7.1 X-Ray Fluorescence Analysis in Medical Sciences.7.2 Total Reflection X-ray Fluorescence for Semiconductors and Thin Films.7.3 X-Ray Spectrometry in Archaeometry.7.4 X-Ray Spectrometry in Forensic Research.7.5 Speciation and Surface Analysis of Single Particles Using Electron-excited X-ray Emission Spectrometry.Index.
164 citations
DSM1
TL;DR: In this paper, the authors used a combined VLA/Parkes radio map to anchor the spectrum at low energy, and model the spectra with synchrotron emission from a cut-off power-law electron distribution, plus a thermal component.
Abstract: SN 1006 is the prototype of shell supernova remnants, in which non-thermal synchrotron emission dominates the X-ray spectrum. The non-thermal emission is due to the cosmic-ray electrons accelerated behind the blast wave. The X-ray synchrotron emission is due to the highest energy electrons, and is thus a tracer of the maximum energy electrons may reach behind a shock. We have put together all XMM-Newton observations to build a full map of SN 1006. The very low brightness above 2 keV in the interior indicates that the bright non-thermal limbs are polar caps rather than an equator. This implies that the ambient magnetic field runs southwest to northeast, along the Galactic plane. We used a combined VLA/Parkes radio map to anchor the spectrum at low energy, and model the spectra with synchrotron emission from a cut-off power-law electron distribution, plus a thermal component. We present radial and azimuthal profiles of the cut-off frequency. The cut-off frequency decreases steeply with radius towards the center and with position angle away from the maximum emission. The maximum energy reached by accelerated particles, as well as their number, must be higher at the bright limbs than elsewhere. This implies interesting constraints for acceleration at perpendicular shocks. Overall the XMM-Newton data is consistent with the model in which the magnetic field is amplified where acceleration is efficient.
146 citations
TL;DR: X-ray photon correlation spectroscopy (XPCS) as mentioned in this paper is a novel technique for the study of slow dynamics in disordered materials that overcomes limitations of visible light scattering techniques such as multiple scattering or limitations in Q-range by using coherent X-rays from third generation synchrotron radiation sources.
TL;DR: By combining magnetic transmission x-ray microscopy with a stroboscopic pump and probe technique using synchrotron radiation, this article was able to image the magnetization dynamics in micron sized magnetic particles on a sub-100 ps time scale with a lateral spatial resolution down to 21 nm.
Abstract: By combining magnetic transmission x-ray microscopy with a stroboscopic pump and probe technique using synchrotron radiation we are able to image the magnetization dynamics in micron sized magnetic particles on a sub-100 ps time scale with a lateral spatial resolution down to 21 nm We report first observations in squared elements indicating locally varying precessional frequencies which are in agreement with micromagnetic simulations The experiment opens a route towards a high spatiotemporal resolution of spin patterns which is needed to understand the microscopic origin of magnetization reversal of micron sized and nano-sized magnetic particles
TL;DR: In this paper, the electron binding energies of solvated anions and cations were investigated at the MBI undulator beamline of the synchrotron radiation facility BESSY and the effect of different countercations (Li+, Na+, K+, and Cs+) and salt concentrations was systematically investigated.
Abstract: The valence band photoemission of aqueous alkali-metal halide solutions is studied for photon energies from 90 to 110 eV. A 6 μm diameter liquid microjet provides a free vacuum surface, allowing water molecules to evaporate without collisions, and hence enables the direct detection of photoelectrons originating from the liquid. The experiments were performed at the MBI undulator beamline of the synchrotron radiation facility BESSY. Here, we focus on the determination of electron binding energies of solvated anions and cations. The effect of different countercations (Li+, Na+, K+, and Cs+), and salt concentrations is systematically investigated. Electron binding energies of the solvated ions are found to differ considerably from those in the gas phase; contrary to intuition, the energies do not depend on the salt concentration. Measured binding energies can be surprisingly well explained within a simple dielectric cavity model. For a NaI aqueous solution, negative surface excess is inferred from the evolut...
TL;DR: Pukhov and Meyer-ter-Vehn as mentioned in this paper showed that a laser wake field in the ''bubble'' regime works as a compact high-brightness source of x-rays.
Abstract: We show that a laser wake field in the ``bubble'' regime [A. Pukhov and J. Meyer-ter-Vehn Appl. Phys. B 74, 355 (2002)], works as a compact high-brightness source of x-rays. The self-trapped relativistic electrons make betatron oscillations in the transverse fields of the bubble and emit a bright broadband x-ray radiation with a maximum about 50 keV. The emission is confined to a small angle of about 0.1 rad. In addition, we make simulations of x-ray generation by an external 28.5 GeV electron bunch injected into the bubble. $\ensuremath{\gamma}$ quanta with up to GeV energies are observed in the simulation in good agreement with analytical results. The energy conversion is efficient, leading to a significant stopping of the electron bunch over 5 mm interaction distance.
TL;DR: In this paper, the effects of O2 inductively coupled plasma (ICP) treatment on the chemical composition and work function of indium-tin-oxide (ITO) surface were investigated.
Abstract: The effects of O2 inductively coupled plasma (ICP) treatment on the chemical composition and work function of indium-tin-oxide (ITO) surface were investigated. Synchrotron radiation photoemission spectroscopy showed that the O2 ICP treatment resulted in the increase of the ITO work function by 0.8 eV. Incorporation of oxygen atoms near the ITO surface during the ICP treatment induced a peroxidic ITO surface, increasing the work function. The enhanced oxidation of a thin Ni overlayer on the O2-ICP-treated sample suggests that preventing the migration of oxygen atoms into the active region of organic light-emitting diodes is important for improving device lifetime.
TL;DR: In this article, the spectrum of synchrotron radiation from the coupling of an electrically charged particle to an external magnetic field in the presence of quantum-gravity effects of the general form (E/MQG)α was derived.
TL;DR: In this paper, the X-ray and gamma-ray spectrum of rotation-powered millisecond pulsars is investigated in a model for acceleration and pair cascades on open field lines above the polar caps.
Abstract: The X-ray and gamma-ray spectrum of rotation-powered millisecond pulsars is investigated in a model for acceleration and pair cascades on open field lines above the polar caps. Although these pulsars have low surface magnetic fields, their short periods allow them to have large magnetospheric potential drops, but the majority do not produce sufficient pairs to completely screen the accelerating electric field. The accelerating particles maintain high Lorentz factors and undergo cyclotron resonant absorption of radio emission, that produces and maintains a large pitch angle, resulting in a strong synchrotron component. The resulting spectra consist of several distinct components: curvature radiation from primary electrons dominating from 1 - 100 GeV, synchrotron radiation from primary and secondary electrons dominating up to about 100 MeV, and much weaker inverse-Compton radiation from primary electrons at 0.1 - 1 TeV. We find that the relative size of these components depends on pulsar period, period derivative, and neutron star mass and radius with the level of the synchrotron component also depending sensitively on the radio emission properties. This model is successful in describing the observed X-ray and gamma-ray spectrum of PSR J0218+4232 as synchrotron radiation, peaking around 100 MeV and extending up to a turnover around several GeV. The predicted curvature radiation components from a number of millisecond pulsars, as well as the collective emission from the millisecond pulsars in globular clusters, should be detectable with AGILE and GLAST. We also discuss a hidden population of X-ray-quiet and radio-quiet millisecond pulsars which have evolved below the pair death line, some of which may be detectable by telescopes sensitive above 1 GeV.
TL;DR: In this article, the authors discuss the probability of realizing the geometrical conditions in which a large polarization is obtained, showing that, for a particularly bright burst such as GRB 021206, the detection of polarization at the first attempt in the Compton drag scenario is not unlikely.
Abstract: The recent claim by Coburn & Boggs to have detected a very high degree of linear polarization in the prompt emission of GRB 021206 has stimulated interest in how much polarization could arise in gamma-ray bursts (GRBs) from synchrotron emission. Alternatively, as Shaviv & Dar have shown, GRB polarization could be produced by inverse Compton scattering in the point-source limit. We discuss polarization from a fireball that upscatters a soft radiation field. We show that, after the proper angular integration, the residual polarization can be large, in some cases approaching the point-source limit. We discuss the probability of realizing the geometrical conditions in which a large polarization is obtained showing that, for a particularly bright burst such as GRB 021206, the detection of polarization at the first attempt in the Compton drag scenario is not unlikely.
TL;DR: In this article, the authors cross-correlate the synchrotron template with 10 and 15 GHz cosmic microwave background observations, and find that its spectrum turns over in a manner consistent with spinning dust emission, falling about an order of magnitude below what the Synchron interpretation would predict.
Abstract: The Wilkinson Microwave Anisotropy Probe (WMAP) team has produced a foreground map that can account for most of the low-frequency Galactic microwave emission in the WMAP maps, tentatively interpreting it as synchrotron emission. Finkbeiner and collaborators have challenged these conclusions, arguing that the WMAP team's "synchrotron" template is in fact dominated not by synchrotron radiation but by some dust-related Galactic emission process, perhaps spinning dust grains, making dramatically different predictions for its behavior at lower frequencies. By cross-correlating this synchrotron template with 10 and 15 GHz cosmic microwave background observations, we find that its spectrum turns over in a manner consistent with spinning dust emission, falling about an order of magnitude below what the synchrotron interpretation would predict.
TL;DR: In this paper, the effect of strain on the band lineups alignments in strained heterostructures is discussed deeply, and the attention is focused on the most important results obtained by several groups in the characterization of semiconductor heterometructures using the following structural SR techniques.
TL;DR: In this paper, the selectivity of the excitation, in terms of energy and polarization, has also facilitated studies of emission anisotropy, and various features observed in resonant emission spectra have been identified.
Abstract: Both synchrotron radiation based soft-X-ray absorption spectroscopy (XAS) and resonant soft-X-ray emission spectroscopy (XES) on a variety of nano-structured systems has yielded characteristic fingerprints. With high-resolution monochromatized synchrotron radiation excitation, resonant inelastic X-ray scattering (RIXS) has emerged as a new source of information about electronic structure and excitation dynamics of nanomaterials. The selectivity of the excitation, in terms of energy and polarization, has also facilitated studies of emission anisotropy. Various features observed in resonant emission spectra have been identified and studied.
TL;DR: In this article, the distribution of molecular structures in a mono-filament was analyzed by micro-beam X-ray diffraction with synchrotron radiation, and it was revealed that the P(3HB) fiber has a new core-sheath structure consistent with two types of molecular conformations.
Abstract: Biodegradable poly[(R)-3-hydroxybutyrate| (P(3HB)) fibers with high tensile strength of 1.32 GPa were processed from ultra-high-molecular-weight P(3HB) by a method combining cold-drawing and two-step-drawing procedures at room temperature. The distribution of molecular structures in a mono-filament was analyzed by micro-beam X-ray diffraction with synchrotron radiation. It was revealed that the P(3HB) fiber has a new core-sheath structure consistent with two types of molecular conformations: a 2 1 helix conformation in the sheath region and a planar zigzag conformation in the core region.
TL;DR: Terahertz scanning near-field infrared microscopy below 1 THz is demonstrated at an electron storage ring using coherent synchrotron radiation in this article, which reveals distinct structural differences in the mesophytic and xerophytic leaves investigated.
Abstract: Terahertz scanning near-field infrared microscopy below 1 THz is demonstrated at an electron storage ring using coherent synchrotron radiation. Spatial resolution below the diffraction limit down to about λ/40 at 2 cm−1 is derived from the transmittance spectra of a conical aperture probe. The potential of the technique is exemplified by imaging wet biological samples. Strongly absorbing living leaves have been imaged in transmittance with a spatial resolution of 130 μm at about 12 cm−1. The THz near-field images reveal distinct structural differences in the mesophytic and xerophytic leaves investigated.
TL;DR: In this article, the photoinduced insulator-to-metal transition in VO2 using time-resolved near-edge x-ray absorption was directly measured using a time-resolution method, which is associated with the transient collapse of the low-temperature band gap.
Abstract: We directly measure the photoinduced insulator-to-metal transition in VO2 using time-resolved near-edge x-ray absorption. Picosecond pulses of synchrotron radiation are used to detect the redshift in the vanadium L3edge at 516 eV, which is associated with the transient collapse of the low-temperature band gap. We identify a two-component temporal response, corresponding to an ultrafast transformation over a 50 nm surface layer, followed by 40 m/s thermal growth of the metallic phase into the bulk.
TL;DR: In this paper, it was shown that for typical parameters expected in the gamma-ray bursts, the observed spectra in the 20-1000 keV energy range can be produced by inverse Compton scattering of the synchrotron radiation in a partially self-absorbed regime.
Abstract: The emission mechanism of gamma-ray bursts (GRBs) is still a matter of debate. The standard synchrotron energy spectrum of cooling electrons F E E -1/2 is much too soft to account for the majority of the observed spectral slopes. An alternative in the form of quasi-thermal Comptonization in a high-compactness source has difficulties in reproducing the peak of the observed photon distribution below a few hundred keV. We show here that for typical parameters expected in the GRB ejecta the observed spectra in the 20-1000 keV energy range can be produced by inverse Compton scattering of the synchrotron radiation in a partially self-absorbed regime. If the particles are continuously accelerated/heated over the lifetime of a source rather than being instantly injected, a prominent peak develops in their distribution at a Lorentz factor y ∼ 30-100, where synchrotron and inverse-Compton losses are balanced by acceleration and heating due to synchrotron self-absorption. The synchrotron peak should be observed at 10-100 eV, whereas the self-absorbed low-energy tail with F E E 2 can produce the prompt optical emission (as in the case of GRB 990123). The first Compton scattering radiation by nearly monoenergetic electrons can then be as hard as F E E 1 , reproducing the hardness of most of the observed GRB spectra. The second Compton peak should be observed in the high-energy gamma-ray band, possibly being responsible for the 10-100 MeV emission detected in GRB 941017. A significant electron-positron pair production reduces the available energy per particle, moving the spectral peaks to lower energies as the burst progresses. The regime is very robust, operates in a broad range of parameter space and can explain most of the observed GRB spectra and their temporal evolution.
TL;DR: Hard x-ray valence band photoemission spectroscopy (PES) is realized using high-energy and high-brilliance synchrotron radiation.
Abstract: Hard x-ray valence band photoemission spectroscopy (PES) is realized using high-energy and high-brilliance synchrotron radiation. High-energy (∼6 keV) excitation results in larger probing depths of photoelectrons compared to conventional PES, and enables a study of intrinsic electronic property of materials in actual device structures much less influenced by surface condition. With this technique, requirements for surface preparation are greatly reduced, if not eliminated. It is a nondestructive tool to determine electronic structure from surface to genuine bulk as shown by a study on SiO2/Si(100). Electronic structure modification related to the ferromagnetism in the diluted magnetic semiconductor Ga0.96Mn0.04N is also observed.
TL;DR: The overall measured polarization performances were highly satisfactory, with measured linear polarization rates of more than 98% in the vertical (horizontal) linear polarization mode and an average 92.1% circular polarization rate for the right- (left)-handed circular polarization mode, which, to the authors' knowledge, are the highest reported values in the VUV range.
Abstract: SU5 is a high-resolution variable-polarization synchrotron radiation (SR) beam line with which linear and circular dichroism experiments are performed in the vacuum ultraviolet (VUV) range (5-40eV), based on an electromagnetic crossed undulator called the Onduleur Plan/Helicoidal du Lure a Induction Electromagnetique (OPHELIE). To get precise knowledge of the polarization state of the emitted SR and to take into account the polarization transformations induced by reflection on the various optics, we set up an in situ VUV polarimeter to provide a precise and complete polarization analysis of the SR atthe sample location. The overall measured polarization performances were highly satisfactory, with measured linear polarization rates of more than 98% (83%) in the vertical (horizontal) linear polarization mode and an average 92.1% (95.2%) circular polarization rate for the right- (left)-handed circular polarization mode, which, to our knowledge, are the highest reported values in the VUV range. Despite some uneven photon energy efficiency, the OPHELIE crossed undulator behaves as expected in terms of polarization, permitting full control of the emitted polarization by manipulation of the vertical-to-horizontal magnetic field ratio (rho(und)) and the relative longitudinal phase (phi(und)).
01 Jun 2004-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this paper, a focused narrowband beam of the synchrotron radiation was used for in-depth analysis of historic and modern paint layers, and fluorescent radiation induced by 21 keV impact radiation was detected by a Si(Li) detector equipped with a polycapillary X-ray lens in con-focal geometry.
Abstract: Focused narrow-band beam of the synchrotron radiation was used for in-depth analysis of historic and modern paint layers. The fluorescent radiation induced by 21 keV impact radiation was detected by a Si(Li) detector equipped with a polycapillary X-ray lens in con-focal geometry. Scanning of the sample was performed by a motorized x–y–z stage. Space resolution of 30 μm was achieved. The procedure of evaluation of concentrations was based on the independent parameter method and included absorption of radiation in the outer layers and secondary fluorescence enhancement induced by hard X-rays of the same and neighboring layers.
Book•
19 Nov 2004
TL;DR: The general aspects of nuclear resonance scattering are discussed in this paper, with a focus on methods and instrumentation, and inelastic and coherent nuclear resonance waveforming techniques, including Coherent Elastic Nuclear Resonant Scattering.
Abstract: Introduction.- General Aspects of Nuclear Resonant Scattering.- Methods and Instrumentation.- Coherent Elastic Nuclear Resonant Scattering.- Inelastic Nuclear Resonant Scattering.- Advanced Scattering Techniques.- Outlook and Perspectives.- Concluding Remarks.
TL;DR: In this paper, the authors presented a synchrotron x-ray diffraction technique by which it is possible to characterize the evolution of mechanical stress in a metallic film thinner than 100 nm at measurement times shorter than 60 s per data point.
Abstract: The mechanical properties of metallic thin films on the nanoscale acquire increasingly more importance as applications in microelectromechanical systems/NEMS as well as microelectronics have reached this size scale. Here, we present a synchrotron x-ray diffraction technique by which it is possible to characterize the evolution of mechanical stress in a metallic film thinner than 100 nm at measurement times shorter than 60 s per data point. This high data acquisition rate is achieved because no relative motions or tilting of specimen, x-ray source and detector (a large-area charge coupled device camera) are required. The technique comprises an initial “sin2 ψ” measurement to establish the absolute stress values followed by periodic “sin2 φ” measurements during straining to determine stress increments. We describe an experimental setup established at the synchrotron radiation source ANKA (Karlsruhe, Germany) which is specifically suited for monitoring the stress evolution during in situ tensile tests on thi...