This PDF file contains the front matter associated with SPIE Proceedings Volume 10760, including the Title Page, Copyright information, Table of Contents, Author and Conference Committee lists.

To preserve the brightness and coherence of x-rays produced by diffraction-limited-storage-ring (DLSR) and free-electron- laser (FEL) light sources, beamline optics must have unprecedented quality. For example, in the case of the most advanced beamlines for the DLSR source under development at the Advanced Light Source (ALS), the ALS-U, we need highly curved x-ray mirrors with surface slope tolerances better than 50–100 nrad (root-mean-square, rms). At the ALS X-Ray Optics Lab (XROL), we are working on the development of a new Optical Surface Measuring System (OSMS) with the required measurement accuracy. The OSMS is capable for the two-dimensional (2D) surface slope metrology over the spatial range from the sub-mm scale to the clear aperture. Usage of different arrangements of the OSMS sensors allows measuring the mirrors in the face-up or side-facing orientation, corresponding to the beamline application. The OSMS translation system and data acquisition software are designed to support multi scan measurement runs optimized for automatic suppression and compensation of instrumental drifts and major angular and spatial systematic errors. Here, we discuss the recent results of the OSMS research and development project. We provide details of the OSMS design and describe results of experimental performance tests of the gantry system. In particular, we show that the system is capable for measurement repeatability with strongly curved mirrors on the level of 20 nrad (rms). The high angular resolution of the OSMS rotational tip-tilt stage is adequate for implementation of instrumental calibration with using the mirror under test as a reference. The achieved measuring accuracy is demonstrated via comparison to metrology with the carefully calibrated Developmental Long Trace Profiler, also available at the XROL.

We describe design guidelines for soft x-ray wavefront sensors and experimentally demonstrate their performance, comparing grating-based lateral shearing interferometry and Hartmann wavefront sensing. We created a compact shearing interferometer concept with a dense array of binary amplitude gratings in a single membrane to support one-dimensional wavefront measurements across a wide wavelength range without the need for longitudinal position adjustment. We find that a common scaling parameter based on wavelength and the distance to the measurement plane guides the design of both systems toward optimal sensitivity. We show preliminary results from recent experiments demonstrating one and two-dimensional wavefront sensing below the Marechal criterion.

In this paper application of laser plasma light sources for testing grazing incidence soft X-ray and EUV optics is presented. The sources are based on laser plasmas produced by irradiation of a gas puff target with nanosecond laser pulses at intensities in the interaction region of about 1011-1014 Wcm-2. The laser pulses are generated using commercially available Nd:YAG lasers generating 4 ns pulses with energy of about 0.8 J or pulses with time duration of 1 ns or 10 ns and energy up to 10 J at 10 Hz repetition rate. The targets are formed by pulsed injection of working gas (Xe, Kr, Ar or their mixtures) in an additional annular stream of He gas under high-pressure using a double-nozzle set up (the double-stream gas puff target approach). Spectral and spatial characteristics of radiation emitted from the sources have been measured. The sources were used to test different grazing incidence optical systems for soft X-ray and EUV spectral ranges, including an axisymmetric ellipsoidal mirror, a pair of axisymmetric paraboloid mirror, a Wolter-type hyperboloid/ellipsoid mirror and a multi-foil “lobster eye” mirror. Results of the metrology studies of these optical systems are presented.

The ESRF Multilayer Laboratory has been operating a thin film x-ray reflectometer for more than 20 years. It is a critical piece of equipment needed to calibrate the multilayer deposition system and to characterize thin film based optical elements. The previous instrument had a number of drawbacks such as limitations in sample size and weight. In addition, the outdated control electronics had to be replaced. The new x-ray reflectometer was designed to handle up to 1 m long samples with a weight of 40 kg while maintaining a positioning accuracy of a few micrometres. The instrument includes a Cu K alpha micro-focus source followed by a Montel multilayer collimator. It can be operated in monochromatic or pink mode by inserting or removing a channel cut crystal monochromator. This work will give an overview on the mechanical and optical design. It will summarize performance benchmarks and give examples of measured x-ray spectra.

Ion-assisted magnetron sputter deposition have been used to deposit Ni/Ti multilayer neutron mirrors. Improved interface widths were obtained by using B₄C doping, to eliminate nanocrystallites by amorphization, and a two-stage modulated ion assistance, to obtain abrupt and smooth interfaces. In situ high-energy wide angle X-ray scattering during multilayer depositions was used to monitor the microstructure evolution and to determine the most favourable growth conditions. Post growth X-ray reflectometry in combination with high resolution transmission electron microscopy confirmed the amorhization and revealed significant improvements in interface widths and reduction of kinetic roughening upon applying B₄C doping and modulated ion assistance during growth. Significant improvement of neutron supermirror performance is predicted by employing this technique.

State of the art optics for Extreme Ultra-Violet Lithography (EUVL) is based on Mo/Si multilayer mirrors (MLMs) integrated with diffusion barriers and capping layers to increase the optics lifetime and experimental reflectance (the current record being 71.3%[1]). In this work, we focus on interface thermodynamics control as a method to optimize the MLM performance. We develop a general framework to select potential elements that could be used as additives in the Si spacing layer to suppress intermixing, while ensuring high EUV reflectivity. We identify rubidium (Rb) as the material giving the highest MLM reflectance and we provide a rigorous estimation of the EUV optical properties of its silicide compounds, RbnSim. We show an increase in optical contrast between RbnSim and Mo via a negative shift of the Si L-edge, and a negligible effect on the absorption coefficient, that remains low. Our calculations indicate that intermixing with Mo can be reduced by 82% and a maximum reflectance of 73.9% can be achieved. Provided that the optics for EUVL must function in a hydrogen environment, we calculate the reflectance also for MLMs with RbH and RbSiH3 as spacing layers. For Mo/RbH MLMs we estimate a full suppression of intermixing and a 74.8% maximum reflectance, while for Mo/RbSiH3 MLMs, if integrated with RbH diffusion barriers, a superior value of 77.4% can be achieved. By implementing the proposed MLM solutions we predict that the optics lifetime can be enhanced and that the total EUVL throughput can be increased up to a factor 2. [1] E. Louis , A.E. Yakshin, T. Tsarfati, F. Bijkerk, "Nanometer interface and materials control for multilayer EUV-optical applications", Progress in Surface Science 86 (2011) 255-294.

The design and realization of a plane-grating monochromator mainly intended for high-energy resolution in the extreme-ultraviolet and soft-X-ray spectral regions is presented. The principal application is the spectral selection of high-order laser harmonics generated in gas combined with the possibility to achieve sub-20-meV bandwidth, approaching synchrotron-like beamlines resolution performances. This geometry has three optical elements: a uniform-line-spaced plane grating illuminated by the converging light coming from a focusing cylindrical mirror and an additional plane mirror that is needed to change the grating subtended angle to keep the system in focus on a fixed slit. The parameters of the focusing mirror are determined to introduce a coma that compensates for the coma given by the grating. A monochromator for the 12-50 eV region has been realized to show the feasibility and the performances of the configuration.

In this paper, we propose a new glass Micropore Optics (MPO), which forms a Wolter type-1 optical system into a single glass substrate without bending or alignment. We call this new X-ray condenser mirror as NXCM. In recent years, lightweight and high-productivity X-ray optics have been demanded for small satellite and detector calibration. We aim to develop a high-performance X-ray MPO by applying our fine patterning and design techniques on the basis of semiconductor-based micromachining technologies. Generally, reducing process steps and cutting out error factors make “productivity” and “resolution” better. It has been expected to form a Wolter type-1 optics directly on a base substrate. Therefore, we focused on the process technology using femtosecond laser irradiation and wet etching, which can form arbitrary fine three-dimensional structure in glass substrate, and applied this technology to MPO fabrication. Using this technique, we successfully achieved to form the two-step oblique grooves machining of 1.7 degrees in the primary stage and 5.1 degrees in the secondary stage with groove widths of 20 μm and 40 μm to the flat glass t 0.5 mm. The groove structure was confirmed by cross-sectional image. The surface roughness of the groove side wall serving as the X-ray reflection surface is expected to be improved by the better scanning of femtosecond laser and the magnetic fluid polishing process. Based on the results, we are proceeding with the production of a condenser mirror prototype while optimizing the coating process and polishing process. In this paper, we report the simulation result of focusing performance and the achievement of the fabrication process in consideration of machining accuracy and error factors. With this method, the higher aspect structure is achieved by stacking several substrates in the optical axis direction or the large area structure is achieved by tiling in the plane direction. The various types of optical structure can be considered with this method.

High angular-resolution imagery (~1” or better) together with good off-axis scattering performance (<1/1000 of the PSF peak at 10” off-axis position) are essential ingredients for revealing energetic plasma processes ongoing in the solar corona during flares. However, imagery of the corona has never been performed with such performance due to severe technical difficulty in fabricating precision Wolter mirrors with a wide field of view exceeding several 100”. We are attempting to realize Wolter mirrors with the above-mentioned performance for future X-ray observations of the Sun. The attempt includes fabrication of engineering mirrors of segmented type to which state-of-the-art precision polish and measurements are applied, followed by X-ray evaluation of focusing performance using BL29XUL parallel X-ray beam line at SPring-8 synchrotron facility. Results of the evaluation are then fed-back to polish/measurements for the subsequent mirrors. Thus far we have successfully fabricated an engineering mirror whose Wolter surfaces 32.5mm x 10mm each for the parabola and hyperbola segments. The mirror focused 8 keV X-rays with the PSF core size ~0.2” HPD (~0.1” FWHM) and with ~3 x 10^(-4) scattering level at 10” off-axis position. Effort has currently been made to increase the area size of the Wolter surfaces towards application to space-borne optics for solar X-ray observations. Status of the current development on the precision Wolter mirrors will be reported together with some future prospects.

A simple one-dimensional wave calculation was implemented for designing a micro-focusing protein crystallography beamline. Wave propagation was successively traced, starting from a Gauss beam as a simple approximation of the undulator light source, to slit as a secondary light source, focusing device replaced with a simple phase shifter, and a focal point. Each source/optics element was divided into the fine segments. Fraunhofer diffraction amplitudes from the segments were summed up at the point on the next element. Source position and emission direction were changed based on the electron beam size and divergence of the storage ring. Intensity distributions at the focal position were finally obtained.

Beam sizes, beam profiles, and photon flux of focused x-rays were calculated by changing the slit size, resulting in the focused beam sizes between 1x1 and 50x50 μm² at the sample position with photon flux of 10¹⁰~10¹³ photons/s with proper photon density of 10¹⁰ photon/s/μm². It satisfies the experimental requirements for the micro-focusing protein crystallography.

We describe our system for generating intense beams of hard X-rays optimized for high throughput phase contrast plant imaging and rapid identification of phenotype in a plant production setting. High peak and average power X-ray beams are generated in a novel regime of ultra-relativistic self-guiding. X-ray beams at 40keV with 4μJ per pulse (30keV – 40keV band) and an average power of 10μW (30keV – 40keV band) are currently produced and used to demonstrate the potential of the LWFA based X-ray sources.

High-repetition-rate self-seeded x-ray free-electron lasers (XFELs), such as the European XFEL in Hamburg (Germany) and upcoming LCLS-II-HE in Stanford (USA) are promising up to three orders of magnitude increase in average spectral flux than what is currently possible with storage-ring-based synchrotron radiation sources [1-4]. This will open up exciting new opportunities for hard x-ray spectroscopic techniques. The new hard x-ray sources with the highest spectral brilliance are offering not only opportunities. There are also challenges, in particular, how to deal with the XFEL beams of very high average and peak power. To address these challenges we have designed, manufactured, and tested diamond channel-cut crystals, to function as high-heat-load, beam-multiplexing, and high-resolution (15-meV bandwidth) monochromators. Diamond channel-cut crystals in the (008) and the (620) orientations were manufactured at the Technological Institute for Superhard and Novel Carbon Materials by application of the newest laser machining technologies [5]. X-ray double-crystal sequential topography and reflectivity studies performed at the Advanced Photon Source demonstrate a close to theoretical performance of the diamond channel cut crystals. We will present details on manufacturing and characterization of the channel-cut crystals. Acknowledgments Work at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357. Work at the Technological Institute for Superhard and Novel Carbon Materials was supported by the Ministry of Education and Science of the Russian Federation, References [1] E. L. Saldin, E. A. Schneidmiller, Yu. Shvyd'ko and M. V. Yurkov, NIM A, 475 (2001) 357 [2] X. Yang and Yu. Shvyd'ko, Phys. Rev. ST Accel. Beams, 16 (2013) 120701 [3] O. Chubar, G. Geloni, V. Kocharyan, A. Madsen, E. Saldin, S. Serkez, Yu. Shvyd’ko, and J. Sutter, J. Synchrotron Radiation, 23 (2016) 410–424 [4] G. Geloni, V. Kocharyan, E. Saldin arXiv:1508.04339 (2015) [5] T. Kolodziej, P. Vodnala, S. Terentyev, V. Blank and Yu. Shvyd'ko, J. Appl. Cryst., 49 (2016) 1240

Monochromatic x-ray backlighting is an essential and basic diagnostic in the research area, such as laser or z-pinch driven inertial confinement fusion, high energy density physics and laboratory astrophysics. A monochromatic hard X-ray backlighting system based on transmission logarithmic spiral crystals has been imposed, where the crystal is employed as a monochromator as well as an optical path deflector by taking advantage of the defining characteristic that all X-ray radiated from the pole of the spiral meet the crystal surface at the same angle. According to the model of Laue logarithmic spiral crystal imaging system and ray tracing method, the imaging principle and characteristics are analyzed theoretically, particularly the distance that the monochromatic beam split from the transmitted beam. We have designed and fabricated a logarithmic spiral quartz 2023 (2d=0.2749nm) crystal. Accordingly, the X-ray imaging system has been setup at 17.479 KeV (Mo Kα line), where the monochromatic image and the polychromatic image can be obtained at the same time. The test data and experimental results are presented and discussed. Compared with the most broadly applied monochromatic x-ray backlighting based on the spherically bent crystal, new developed imaging system can achieve higher photo energy and broader field of view.

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.