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Conley, Raymond

Publications and source records attributed to Conley, Raymond.

13 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

X-ray back-diffraction: can we further increase the energy resolution by tuning the energy slightly below that of exact backscattering?

X-ray beams at energies tuned slightly below that of exact backscattering (extreme conditions, where X-ray back-diffraction is almost extinguished - called residual XBD) are better focused if the experiment is carried out at lower energies in order to avoid multiple-beam diffraction effects. Following previous work by the authors [Honnicke, Conley, Cusatis, Kakuno, Zhou, Bouet, Marques & Vicentin (2014). J. Appl. Cryst.47, 1658-1665], herein efforts are directed towards characterizing the residual XBD beam of an ultra-thin Si 220 crystal (UTSiXTAL) at similar to 3.2 keV. To achieve the residual XBD condition the UTSiXTAL was cooled from 310 to 273 K. The results indicate that under this extreme condition the energy resolution can be further improved. Issues with the energy resolution measurements due to incoming beam divergence and the ultra-thin crystal flatness are discussed.

low-energy X-ray back-diffraction↗
DOE OSTI2018

Damage thresholds for blaze diffraction gratings and grazing incidence optics at an X-ray free-electron laser

The Linac Coherent Light Source is upgrading its machine to high repetition rate and to extended ranges. Novel coatings, with limited surface oxidation, which are able to work at the carbon edge, are required. In addition, high-resolution soft X-ray monochromators become necessary. One of the big challenges is to design the mirror geometry and the grating profile to have high reflectivity (or efficiency) and at the same time survive the high peak energy of the free-electron laser pulses. For these reasons the experimental damage threshold, at 900 eV, of two platinum-coated gratings with different blazed angles has been investigated. The gratings were tested at 1° grazing incidence. To validate a model for which the damage threshold on the blaze grating can be estimated by calculating the damage threshold of a mirror with an angle of incidence identical to the angle of incidence on the grating plus the blaze angle, tests on Pt-coated substrates have also been performed. The results confirmed the prediction. Uncoated silicon, platinum and SiB 3 (both deposited on a silicon substrate) were also investigated. In general, the measured damage threshold at grazing incidence is higher than that calculated under the assumption that there is no energy transport from the volume where the photons are absorbed. However, it was found that, for the case of the SiB 3 coating, the grazing incidence condition did not increase the damage threshold, indicating that the energy transport away from the extinction volume is negligible.

43 PARTICLE ACCELERATORS↗
DOE OSTI2018

A dual-bandwidth multilayer monochromator system

This paper reports on a planned upgrade to the capabilities of the Illinois Institute of Technology’s BioCAT undulator beamline in an effort to increase the photon flux 10 to 100-fold. This is accomplished by the addition of a double multilayer monochromator (MLM) system complementing the existing cryogenically-cooled double crystal silicon monochromator system. The water-cooled MLMs are designed and fabricated with each having two coated stripes to deliver a 12 keV undulator beam with either 1.0% or 0.5% energy bandwidths (BW). To simplify the mechanical design and operation of the MLM system, the two coatings have been designed with the same period thickness so that the BW selection is accomplished (at the same Bragg angle) by a mere horizontal translation of the MLMs. The challenge has been to find a pair of coatings that provide the desired BWs with high reflectivity at the same incident angle. This was achieved using MoSi2/B4C and Mo/MoSi2/B4C/MoS2 multilayers at an angle of 1.194°. The bandwidths and reflectivities attained are 0.52 and 83.33% for the former and 0.86 and 75.9% for the latter. Details are provided.

X-ray optics, multilayer, coating, tuning, reflect↗
DOE OSTI2016

X-ray optics testing beamline 1-BM at the advanced photon source

Beamline 1-BM at the APS has been reconfigured in part for testing of synchrotron optics with both monochromatic and white beams. Operational since 2013, it was reconfigured to accommodate users of the APS as well as users from other DOE facilities. Energies between 6 and 28 keV are available. The beamline was reconfigured to remove two large mirrors and to provide a 100 mm wide monochromatic beam at 54 m from the source. In addition a custom white beam shutter was implemented for topography exposures as short as 65 millisec over the full available horizontal width. Primary agendas include both white beam and monochromatic beam topography, Talbot grating interferometry, and tests of focusing optics. K-B mirrors, MLLs, and FZPs have been characterized. Measurements of the spatial coherence lengths on the beamline were obtained with Talbot interferometry. Topography data has been reported.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

1.5 nm fabrication of test patterns for characterization of metrological systems

Any metrology tool is only as good as it is calibrated. The characterization of metrology systems requires test patterns at a scale about ten times smaller than the measured features. The fabrication of patterns with linewidths down to 1.5 nm is described. The test sample was designed in such a way that the distribution of linewidths appears to be random at any location. This pseudorandom test pattern is used to characterize dimensional metrology equipment over its entire dynamic range by extracting the modulation transfer function of the system. The test pattern contains alternating lines of silicon and tungsten silicide, each according to its designed width. As a result, the fabricated test samples were imaged using a transmission electron microscope, a scanning electron microscope, and an atomic force microscope. (C) 2015 American Vacuum Society.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

Diffraction properties of multilayer Laue lenses with an aperture of 102 µm and WSi 2 /Al bilayers

We report on the characterization of a multilayer Laue lens (MLL) with large acceptance, made of a novel WSi 2 /Al bilayer system. Fabrication of multilayers with large deposition thickness is required to obtain MLL structures with sufficient apertures capable of accepting the full lateral coherence length of x-rays at typical nanofocusing beamlines. To date, the total deposition thickness has been limited by stress-buildup in the multilayer. We were able to grow WSi2/Al with low grown-in stress, and asses the degree of stress reduction. X-ray diffraction experiments were conducted at beamline 1-BM at the Advanced Photon Source. We used monochromatic x-rays with a photon energy of 12 keV and a bandwidth of $ΔE/\atop {E}$ = 5.4 • 10 -4 . The MLL was grown with parallel layer interfaces, and was designed to have a large focal length of 9.6 mm. The mounted lens was 2.7 mm in width. We found and quantified kinks and bending of sections of the MLL. Sections with bending were found to partly have a systematic progression in the interface angles. We observed kinking in some, but not all, areas. The measurements are compared with dynamic diffraction calculations made with Coupled Wave Theory. Data are plotted showing the diffraction efficiency as a function of the external tilting angle of the entire mounted lens. This way of plotting the data was found to provide an overview into the diffraction properties of the whole lens, and enabled the following layer tilt analyses.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Efficiency of a multilayer-Laue-lens with a 102 μm aperture

A multilayer-Laue-lens (MLL) comprised of WSi 2 /Al layers stacked to a full thickness of 102 microns was characterized for its diffraction efficiency and dynamical diffraction properties by x-ray measurements made in the far field. The achieved aperture roughly doubles the previous maximum reported aperture for an MLL, thereby doubling the working distance. Negative and positive first orders were found to have 14.2 % and 13.0 % efficiencies, respectively. A section thickness of 9.6 μm was determined from Laue-case thickness fringes in the diffraction data. A background gas consisting of 90 % Ar and 10 % N 2 was used for sputtering. This material system was chosen to reduce grown-in stress as the multilayer is deposited. Although some regions of the full MLL exhibited defects, the presently reported results were obtained for a region devoid of defects. The data compare well to dynamical diffraction calculations with Coupled Wave Theory (CWT) which provided confirmation of the optical constants and densities assumed for the CWT calculations.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Achieving Hard X-ray Nanofocusing Using a Wedged Multilayer Laue Lens

Here, we report on the fabrication and the characterization of a wedged multilayer Laue lens for x-ray nanofocusing. The lens was fabricated using a sputtering deposition technique, in which a specially designed mask was employed to introduce a thickness gradient in the lateral direction of the multilayer. X-ray characterization shows an efficiency of 27% and a focus size of 26 nm at 14.6 keV, in a good agreement with theoretical calculations. Our results indicate that the desired wedging is achieved in the fabricated structure. Furthermore, we anticipate that continuous development on wedged MLLs will advance x-ray nanofocusing optics to new frontiers and enrich capabilities and opportunities for hard X-ray microscopy.

42 ENGINEERING↗
DOE OSTI2011

Synchrotron X-ray tests of an L-shaped laterally graded multilayer mirror for the analyzer system of the ultra-high-resolution IXS spectrometer at NSLS-II

Characterization and testing of an L-shaped laterally graded multilayer mirror are presented. This mirror is designed as a two-dimensional collimating optics for the analyzer system of the ultra-high-resolution inelastic X-ray scattering (IXS) spectrometer at National Synchrotron Light Source II (NSLS-II). The characterization includes point-to-point reflectivity measurements, lattice parameter determination and mirror metrology (figure, slope error and roughness). Here, the synchrotron X-ray test of the mirror was carried out reversely as a focusing device. The results show that the L-shaped laterally graded multilayer mirror is suitable to be used, with high efficiency, for the analyzer system of the IXS spectrometer at NSLS-II.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: expanding the application range

A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47, 073602 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A616, 172 (2010)]. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters.

42 ENGINEERING↗
DOE OSTI2010

Characterization of electron microscopes with binary pseudo-random multilayer test samples

Verification of the reliability of metrology data from high quality x-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested [Proc. SPIE 7077-7 (2007), Opt. Eng. 47(7), 073602-1-5 (2008)} and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [Nucl. Instr. and Meth. A 616, 172-82 (2010)]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2010

Calibration of the modulation transfer function of surface profilometers with binary pseudo-random test standards: Expanding the application range

A modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays [Proc. SPIE 7077-7 (2007), Opt. Eng. 47(7), 073602-1-5 (2008)] has been proven to be an effective MTF calibration method for a number of interferometric microscopes and a scatterometer [Nucl. Instr. and Meth. A 616, 172-82 (2010]. Here we report on a significant expansion of the application range of the method. We describe the MTF calibration of a 6 inch phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters.

47 OTHER INSTRUMENTATION↗