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Aperiodic multilayers have important applications in hard X-rays astronomical observations due to their broadband responses. This paper presents an optimization model of Pt/C power-law graded stack multilayers using the IMD software. The reflectivity expression of multilayers was derived from the reflection theory of X-ray multilayers and Fresnel recursion formulas. Then, the effects of maximum bi-layer thickness (dmax), ratio of high-density material thickness to bi-layer thickness (Γ), power-law index (c), number of bi-layers (N), grazing incidence angle (ϕ), interfacial roughness (σ), and photon energy (E) on the reflectivity were analyzed. The calculation results showed that the dmax, Γ and c control the shift of response range, absorption peak and Bragg peaks, respectively. And the decrease of N and increase of ϕ and σ can result in the reduction of reflectivity at different energies. Additionally, an optimized multilayer structure was proposed according to the extremum of merit function, which can achieve a broadband reflectivity of no less than 0.6 from 1keV up to 80keV. These results can provide important references for the response characteristic analysis and optimization design of multilayers. [ABSTRACT FROM AUTHOR]

The paper proposes an X-ray optical scheme of a lithograph with a transmissive dynamic mask and a synchrotron radiation source. The image of a dynamic mask in the form of holes of small diameter is transferred with a decrease to a plate with a resist using a Schwarzschild projection lens. The formation of a topological pattern will occur due to the coordinated operation of the system for scanning a plate with a resist and a microelectromechanical system of a transmissive type. Objectives with a reduction of 10 and 20 times for obtaining 10–20 nm images of 200 nm holes of the dynamic mask are considered. The scheme of illumination of the mask is calculated, which provides uniform illumination on a field of 10 × 10 mm2. For the synchrotron Siberia-2 of the KISI on a bending magnet, the expected productivity of the lithograph will be up to 1/14 of a plate with a diameter of 100 mm per hour. [ABSTRACT FROM AUTHOR]

In this study, double-multilayer monochromators that generate intense, high-energy, pink X-ray beams are designed, installed and evaluated at the SPring-8 medium-length (215 m) bending-magnet beamline BL20B2 for imaging applications. Two pairs of W/B4C multilayer mirrors are designed to utilize photon energies of 110 keV and 40 keV with bandwidths of 0.8% and 4.8%, respectively, which are more than 100 times larger when compared with the Si double-crystal monochromator (DCM) with a bandwidth of less than 0.01%. At an experimental hutch located 210 m away from the source, a large and uniform beam of size 14 mm (V) × 300 mm (H) [21 mm (V) × 300 mm (H)] was generated with a high flux density of 1.6 × 109 photons s−1 mm−2 (6.9 × 1010 photons s−1 mm−2) at 110 keV (40 keV), which marked a 300 (190) times increase in the photon flux when compared with a DCM with Si 511 (111) diffraction. The intense pink beams facilitate advanced X-ray imaging for large-sized objects such as fossils, rocks, organs and electronic devices with high speed and high spatial resolution.

A high-irradiance illumination system with normal-incidence multilayer mirrors is developed. The system consists of two concave Mo/Si multilayer mirrors with aspherical substrates that provide critical illumination by imaging a laser-produced plasma (LPP) light source at a wavelength of 13.6 nm with a magnification of almost unity. By effectively correcting spherical aberration, a raytracing computation indicates that the irradiance on the sample can be increased by about four times compared to that for a conventional system with spherical mirrors. We experimentally confirmed the enhancement by combining a LPP light source with aspherical mirrors fabricated by magneto rheological finishing. [ABSTRACT FROM AUTHOR]

Soft X-ray spectroscopy of the Sun is an important tool to understand the coronal dynamics and composition. The solar coronal X-ray spectrum below 1 keV is the least explored with high-resolution spectroscopy. Recent observations with Hinode XRT using coarse spectroscopy along with high-resolution imaging have shown that abundances in the coronae have variability associated with structures on the Sun. Disk averaged abundances with better spectral resolution spectrometers show time variability associated with flares. Both spatial and temporal variabilities seem to be related to changes in the magnetic field topology. Understanding such short term variabilities is necessary to model the underlying dynamics and mixing of material between different layers of the Sun. A Sensitive high-resolution spectrometer that covers the range in plasma temperatures and emission line complexes would uniquely reveal the entire evolution of flares. We are investigating a design of a multi-layer mirror-based X-ray spectrograph in the spectral range from 0.5 to 7 keV. The instrument operates in four asynchronous spectral channels operating one at a time. The multi-layer mirror placed at the focus of a Wolter type I telescope reflects a narrow band X-rays to the CCD which is placed at Nasmyth defocus. Converging X-rays from the front end optics helps to increase the spectral range of each channel while preserving the spectral resolution. This design is estimated to achieve a spectral resolution of 20 eV in the spectral range of 0.5–7 keV. With such high spectral resolution, we can resolve individual spectral features e.g., 6.7 keV Fe complex which can be used to diagnose high-temperature transient plasma during flares. The instrument design estimated performance and the science capabilities of this instrument will be discussed in detail in the paper.

Featured Application: The designed periodic multilayer, implemented on electron microprobe analyzers or scanning electron microscopes, will improve wavelength dispersive X-ray spectroscopic investigations in the range of the Li K emission. X-ray spectroscopy of lithium is very difficult, even impossible, with wavelength dispersive spectrometers commonly deployed on scanning electron microscopes or electron microprobe analyzers. This is due to the absence of crystals and lack of efficient periodic multilayer for this spectral range, around 50 eV. To address this issue, we propose using a Be/Si/Al multilayer having a period of about 29 nm. The multilayer was deposited by magnetron sputtering and its reflectivity measured as a function of the glancing angle in the spectral range of the Li K emission and as a function of the incident energy up to ~200 eV. This characterization demonstrates that the designed multilayer is suitable to efficiently perform spectroscopy in the range of the Li K emission in terms of reflectance (0.32 at 51.5 eV), bandwidth (around 3.5 eV) and rejection of high order diffracted radiation. [ABSTRACT FROM AUTHOR]

X-ray spectroscopy of lithium is very difficult, even impossible, with wavelength dispersive spectrometers commonly deployed on scanning electron microscopes or electron microprobe analyzers. This is due to the absence of crystals and lack of efficient periodic multilayer for this spectral range, around 50 eV. To address this issue, we propose using a Be/Si/Al multilayer having a period of about 29 nm. The multilayer was deposited by magnetron sputtering and its reflectivity measured as a function of the glancing angle in the spectral range of the Li K emission and as a function of the incident energy up to ~200 eV. This characterization demonstrates that the designed multilayer is suitable to efficiently perform spectroscopy in the range of the Li K emission in terms of reflectance (0.32 at 51.5 eV), bandwidth (around 3.5 eV) and rejection of high order diffracted radiation.

In the design of a W/C multilayer mirror, we applied a trilayer model to consider the interdiffusion of tungsten and carbon on the W-on-C interface and investigated the first Bragg angle and its reflectivity. As the interdiffusion thickness of a W/C multilayer mirror increased, the first Bragg angle and the reflected X-ray energy increased. However, as the period thickness of the W/C multilayer mirror increased, the effects of the interdiffusion became less pronounced. The criteria for the use of either the bilayer or the trilayer models for the design of W/C multilayer mirrors were presented for various period thicknesses. The trilayer model would be useful for the design of multilayer mirrors with a small period thickness of less than approximately 4.0 nm at an interdiffusion of 0.28 nm. [ABSTRACT FROM AUTHOR]

Driven by the growing demand for large-size x-ray mirrors used in synchrotron radiation and free-electron laser facilities, a linear deposition system based on magnetron sputtering technique is built. The layer growth quality and thickness uniformity are optimized by adding masks in front of the cathode to reduce the oblique-incidence particles and tune the sputtering flux distribution. Based on this, a 0.5-m-length W/Si multilayer mirror is demonstrated. The multilayer has a d-spacing of 3 nm and a bilayer number of 60. The surface roughness of the multilayer is only 0.33 to 0.25 nm in the spatial frequency range of 3.0 × 10-3 to 1.0 μm-1, and the average interface width is 0.32 nm. The hard x-ray reflectivity and uniformity of the large mirror were characterized at the Optics Beamline in Shanghai Synchrotron Radiation Facility. A maximum reflectivity of 62.5% and 62.7% was measured at 8 and 18 keV, respectively, with an angular resolution of Δθ/θ ¼ 2.7%. The d-spacing uniformity over the 0.5-m-length and 60-mm-width area of the mirror is 1.0% and 1.2% (peak-tovalley), respectively. These results indicate a good and uniform quality of the nanoscale multilayer over the large mirror area. The measured second- and third-order reflectivities of the multilayer are more than 2 orders magnitude lower than the first order, implying a good suppression of high harmonics in the monochromator application. [ABSTRACT FROM AUTHOR]

Extreme ultraviolet (XUV) and X‐ray free‐electron lasers enable new scientific opportunities. Their ultra‐intense coherent femtosecond pulses give unprecedented access to the structure of undepositable nanoscale objects and to transient states of highly excited matter. In order to probe the ultrafast complex light‐induced dynamics on the relevant time scales, the multi‐purpose end‐station CAMP at the free‐electron laser FLASH has been complemented by the novel multilayer‐mirror‐based split‐and‐delay unit DESC (DElay Stage for CAMP) for time‐resolved experiments. XUV double‐pulses with delays adjustable from zero femtoseconds up to 650 picoseconds are generated by reflecting under near‐normal incidence, exceeding the time range accessible with existing XUV split‐and‐delay units. Procedures to establish temporal and spatial overlap of the two pulses in CAMP are presented, with emphasis on the optimization of the spatial overlap at long time‐delays via time‐dependent features, for example in ion spectra of atomic clusters. [ABSTRACT FROM AUTHOR]

Extreme ultra violet lithography (EUVL) is no longer a future technology but is going to be inserted into mass production of semiconductor devices of 7 nm technology node in 2018. EUVL is an extension of optical lithography using extremely short wavelength (13.5 nm). This short wavelength requires major modifications in the optical systems due to the very strong absorption of EUV light by materials. Refractive optics can no longer be used, and reflective optics is the only solution to transfer image from mask to wafer. This is why we need the multilayer (ML) mirror-based mask as well as an oblique incident angle of light. This paper discusses the principal theory on the EUV mask design and its component materials including ML reflector and EUV absorber. Mask shadowing effect (or mask 3D effect) is explained and its technical solutions like phase shift mask is reviewed. Even though not all the technical issues on EUV mask are handled in this review paper, you will be able to understand the principles determining the performance of EUV masks. [ABSTRACT FROM AUTHOR]

• Stabilization of Sc/Si/Al mirror reflectance decrease after 40 months of stored in air. • Increase in the amount of impurities - the main reason of the mirror reflectivity loss. • Si and ScN x interlayers have no effect on the temporal stability of the Sc/Al mirror. • MoSi 2 cap layer thickness within 3–6 nm does not affect the mirror temporal stability. Observation of a sample of Si/Al/Sc mirror with a MoSi 2 protective cap layer, which was stored in air for 40 months, showed that the peak reflectivity at a wavelength of 58.4 nm during this period decreased from 32 % to 20.5 %, and over the last 20 months of observation—from 21.5 % to 20.5 %, which indicates a significant decrease in the rate of decline and almost stabilization of the peak reflectivity at the level of 20 %. The spectral reflection peak width of this mirror at half maximum has not changed over the past 20 months and amounted to 6.3 nm. The given data of secondary ion mass spectrometry and grazing incidence X-ray reflectometry show that the decrease in reflectance of Si/Al/Sc multilayer mirrors with a MoSi 2 protective cap layer is mainly due to an increase in the amount of impurities (oxygen and carbon) in the structure and on the surface of the mirrors and, to a lesser extent, due to the broadening of the interlayer boundaries. Comparison of the rate of decrease in reflectance at 58.4 nm of Sc/Al mirrors with interlayers of silicon and nitride scandium and a MoSi 2 cap layer indicates that neither the material and thickness of the interlayer nor the thickness of the protective MoSi 2 cap layer within 3–6 nm have a significant effect on this rate. [ABSTRACT FROM AUTHOR]

On imaging for full-field extreme ultraviolet microscopy, the Fresnel number on the image plane falls below unity since a high magnification objective remarkably reduces the numerical aperture on the image plane, while the Fresnel number on the object plane is relatively large in most cases. To understand imaging with the high-magnification objective with far different Fresnel numbers on these two planes, in this study, we experimentally confirmed the imaging properties by observing through-focus images of a point object on both the object and image sides. The experiments showed that, the defocus characteristics on the image side were found to be asymmetric with respect to the detector location, while those on the object side were found to be symmetric with respect to the object distance. To explain these unconventional imaging properties, we proposed a simple analytical model considering the two different Fresnel numbers on the high-magnification objective. The model showed that the magnification would vary even if the image plane was within the focal depth, and this yields the asymmetric defocus characteristics. At the same time, when we moved an object along an optical axis, the defocus aberrations were represented by the conventional equation for a large-Fresnel-number system, which can well explain the symmetric defocus characteristics on the object side. We also discuss the effect of an additional phase factor that modifies the amplitude on the image plane. [ABSTRACT FROM AUTHOR]

Ptychography is a lensless imaging technique that is aberration-free and capable of imaging both the amplitude and the phase of radiation reflected or transmitted from an object using iterative algorithms. Working with extreme ultraviolet (EUV) light, ptychography can provide better resolution than conventional optical microscopy and deeper penetration than scanning electron microscope. As a compact lab-scale EUV light sources, high harmonic generation meets the high coherence requirement of ptychography and gives more flexibilities in both budget and experimental time compared to synchrotrons. The ability to measure phase makes reflection-mode ptychography a good choice for characterising both the surface topography and the internal structural changes in EUV multilayer mirrors. This paper describes the use of reflection-mode ptychography with a lab-scale high harmonic generation based EUV light source to perform quantitative measurement of the amplitude and phase reflection from EUV multilayer mirrors with engineered substrate defects. Using EUV light at 29.6 nm from a tabletop high harmonic generation light source, a lateral resolution down to ∼ 88 nm and a phase resolution of 0. 08 rad (equivalent to topographic height variation of 0.27 nm) are achieved. The effect of surface distortion and roughness on EUV reflectivity is compared to topographic properties of the mirror defects measured using both atomic force microscopy and scanning transmission electron microscopy. Modelling of reflection properties from multilayer mirrors is used to predict the potential of a combination of on-resonance, actinic ptychographic imaging at 13.5 nm and atomic force microscopy for characterising the changes in multilayered structures. [ABSTRACT FROM AUTHOR]

Advances in resonant inelastic X-ray scattering (RIXS) have come in lockstep with improvements in energy resolution. Currently, the best energy resolution at the Ir L3-edge stands at ∼25 meV, which is achieved using a diced Si(844) spherical crystal analyzer. However, spherical analyzers are limited by their intrinsic reflection width. A novel analyzer system using multiple flat crystals provides a promising way to overcome this limitation. For the present design, an energy resolution at or below 10 meV was selected. Recognizing that the angular acceptance of flat crystals is severely limited, a collimating element is essential to achieve the necessary solid-angle acceptance. For this purpose, a laterally graded, parabolic, multilayer Montel mirror was designed for use at the Ir L3-absorption edge. It provides an acceptance larger than 10 mrad, collimating the reflected X-ray beam to smaller than 100 µrad, in both vertical and horizontal directions. The performance of this mirror was studied at beamline 27-ID at the Advanced Photon Source. X-rays from a diamond (111) monochromator illuminated a scattering source of diameter 5 µm, generating an incident beam on the mirror with a well determined divergence of 40 mrad. A flat Si(111) crystal after the mirror served as the divergence analyzer. From X-ray measurements, ray-tracing simulations and optical metrology results, it was established that the Montel mirror satisfied the specifications of angular acceptance and collimation quality necessary for a high-resolution RIXS multi-crystal analyzer system. [ABSTRACT FROM AUTHOR]

Planarizing or smoothing over nodular defects in multilayer mirrors can be accomplished by a discrete deposit-and-etch process that exploits the angle-dependent etching rate of optical materials. Typically, nodular defects limit the fluence on mirrors irradiated at 1064 nm with 10 ns pulse lengths due to geometrically- and interference-induced light intensification. Planarized hafina/silica multilayer mirrors have demonstrated > 125 J/cm 2 laser resistance for single-shot testing and 50 J/cm 2 for multi-shot testing for nodular defects originating on the substrate surface. Two planarization methods were explored: thick planarization layers on the substrate surface and planarized silica layers throughout the multilayer in which only the silica layers that are below one half of the incoming electric field value are etched. This paper also describes the impact of planarized defects that are buried within the multilayer structure compared to planarized substrate particulate defects. [ABSTRACT FROM AUTHOR]

Abstract: In order to follow and understand time dependent contamination growth on multilayer mirrors for extreme ultraviolet (EUV) lithography applications, particular heterosystems were investigated with X-ray Photoemission Spectroscopy (XPS). Diverse capping layers can be used to terminate EUV multilayer mirrors to protect the underlying multilayer stack, e.g. Ru metal. In XPS problems were encountered when analyzing spectra as the core-level signals of Ru and C overlap. Further, Ru was not only present as pure metal, but also in its oxidized state. Disentangling the overlapping XPS spectra was achieved by application of factor analysis (FA) yielding not only the spectra of each component but also the according weights. Thus a model for the time dependent contamination growth was developed. This model was cross checked by advanced inelastic background analysis. Both methods displayed a way to unravel overlapping data sets and for deducing multilayer composition models. [Copyright &y& Elsevier]

Abstract: The progress in development of an experimental setup for investigating the ultra-soft X-rays and vacuum ultraviolet radiation generated at incidence of relativistic electrons on the surface of multilayer X-ray mirror is described. The results of the first test experiments carried out for observing the contribution of parametric radiation in generated X-rays are presented. [Copyright &y& Elsevier]

Abstract: The electromagnetic field in subwavelength resonant diffractive optical elements is so concentrated that a very shallow surface corrugation obtained by wet chemical micro–nano-etching is sufficient to give rise to high contrast diffraction effects allowing a high wavelength-, polarization- or transverse-mode-selectivity which is not achievable by conventional diffractive elements. Two examples of polarizing laser mirrors at both extremes of the optical spectrum with wet-etched grating bypassing and cutting through the 1D photonic crystal are demonstrated. [Copyright &y& Elsevier]

Abstract: We have developed non-periodic Cr/Sc multilayer mirrors specifically designed to reflect energy photons between 2 and 4keV with a pre-defined reflectivity profile. Furthermore, these mirrors have to work as filters in the 1–2keV and 4–12keV energy bandpass with a reflectivity as low as possible in these bandwidths. The mirrors were designed and optimized with the help of a commercial calculation code. Numerous combinations of layers have been investigated with two or three different materials in the multilayer. The interfacial effect, leading to thickness modifications, has been investigated. Layer thicknesses were accurately controlled, taking into account compaction effect at interfaces. The best results lead to non-periodic mirrors dedicated to work at 1.5° grazing incidence with a reflectivity above 15% in almost the entire energy range 2–4keV and lower than 1% outside, except in the total reflection zone. The final choice of material was made from the experimental knowledge of corresponding layer deposited behavior. The multilayers have been deposited by magnetron sputtering. Grazing-incidence X-ray reflectance at 8.05keV (0.154nm) and at the Physikalisch-Technische Bundesanstalt laboratory (PTB) at the synchrotron radiation facility BESSY II in Berlin for X-ray reflectance over the whole range were used both in order to characterize the multilayers (thicknesses, complex indices, and roughnesses). The final results show good agreement with the requested reflectivity profile. [Copyright &y& Elsevier]

We have investigated the use of atomic-hydrogen-based cleaning to remove Sn contamination from extreme ultraviolet (EUV) multilayer mirrors. Mo and Si surfaces were cleaned at a relatively slow rate due to catalyzed dissociation of tin hydride on these surfaces. Mo/Si mirrors with B4C and Si3N4 cap layers and DLC-terminated DLC/Si mirrors showed complete removal of 10 nm Sn in 20 sec with full restoration of EUV reflectance. In addition, a prolonged cleaning treatment of 300 sec of a DLC/Si mirror resulted in only a minor EUV peak reflection loss of 1.2% absolute and no significant changes in infrared reflectance. [ABSTRACT FROM AUTHOR]

Abstract: We have developed non-periodic W/SiC multilayer mirrors (“supermirrors”) specifically designed to reflect photons between 2 and 10keV. The mirrors were designed and optimized with a homemade calculation code. The supermirrors are designed to work at a nominal 0.7° grazing incidence with reflectivity above 35% in almost the entire energy range. The multilayers have been deposited by magnetron sputtering. Grazing incidence X-ray reflectance at 8keV (0.154nm) was made using a laboratory source. Reflectance measurement over the whole range was made at Physikalisch-Technische Bundesanstalt laboratory (PTB), the synchrotron radiation facility BESSY II, in Berlin. In addition to X-ray reflectance, multilayer thickness, refractive indices and roughness were characterized. The experimental results show good agreement with theoretical computations. [ABSTRACT FROM AUTHOR]

Abstract: Ru-capped Mo/Si multilayer mirrors were irradiated by EUV in a vacuum atmosphere with ethanol or decane gas, and their reflectivity changes by contamination were investigated by changing the amount of introduced gas. The reflectivity hardly decreased by EUV irradiation in the ethanol-introduced atmosphere. On the other hand, the reflectivity decreased by about 5% in the decane-introduced atmosphere at a decane pressure of P Decane =1.3×10−4 Pa, an EUV power of about 200mW/mm2, and an EUV dose of 150J/mm2. EUV irradiation to the Ru-capped multilayer mirrors was also performed in the presence of water vapor and decane. The surface oxidation by EUV irradiation with a water vapor pressure of was controlled by the introduction of decane at a pressure of P Decane =7.0×10−7 to 1.3×10−6 Pa. [Copyright &y& Elsevier]

In the ICF experiments, spectrum of X-ray includes a lot of information. Multilayer spectrometer, an X-ray energy spectrometer with high resolution, is composed of multilayer mirrors with different period thickness, some suitable filters and X-ray detectors (XRD). In this paper, a multilayer spectrometer is developed, which will be applied in ICF experiments. The specifications are as follows: Energy range: 100~1500 eV; Channel number: 8; Vacuum degree: 3E–3Pa. The project was proposed on the base of design demand. Then the model was set up and analyzed. This multilayer spectrometer is the most advanced domestic model, and it is very different from the overseas ones. [ABSTRACT FROM AUTHOR]

Abstract: Studying the distribution of He+ in Earth''s plasmasphere by detecting its resonantly scattered emission at 304Å will record the structure and dynamics of the cold plasma in Earth''s plasmasphere on a global scale. EUV imaging systems usually utilizes near-normal incidence optics including multilayer mirror and filter. In this paper, the space condition of the Earth''s plasmasphere to confirm the expected performance of mirror were analyzed. In order to achieve higher response at 304Å and reduce 584Å radiation for the optical system, a new multilayer coating of Mo/Si with UO2 was developed. Based on optical constants of Mo, Si and UO2, we used a simplest method to compute the reflectance of this new multilayer mirror range from 100 to 584Å. The results show the desirable thickness of UO2 is 17Å, and the multilayer mirror has a high reflectance of 26.10% at 304Å and a low reflectance of 0.52% at 584Å. [Copyright &y& Elsevier]

Abstract: W/Si aperiodic multilayer mirrors were developed at the Commissariat à l’Energie Atomique (CEA-DIF) in collaboration with the Laboratoire des Matériaux et de Microélectronique de Provence (L2MP). These “super-mirrors” [F. Mezei, Commun. Phys. 2 (1977) 41. ; E. Spiller, Appl. Phys. Lett. 20 (1972) 365. ], named Ma151 and Ma152, were designed to work at 0.6° grazing incidence with a high reflectivity in a large photon energy range for X-ray energies above 5keV. The Ma151 multilayer will be integrated into a high-resolution X-ray microscope the so-called Plasma Imageur X pour les Expériences Laser Megajoule (PIXEL). This prototype will be used for spatial and time resolved imaging of dense and warm fusion plasmas produced during inertial confinement fusion (ICF) experiments at the future Laser Megajoule facility. Experimental results obtained at the Physikalisch-Technische Bundesanstalt (PTB) laboratory at the synchrotron radiation facility BESSY II in Berlin, show that the Ma151 average reflectivity is above 40% in almost the entire energy range 5–10keV. From the measurements on the mirror MA152, a reflectivity above 15% can be expected in the energy range 7.2–14keV. The experimental results show good agreement with theoretical computations from the XR-Vision [T. Moreno, Software X-ray Vision Applied by Caminotec, Paris, France. ] code and demonstrate the ability to produce such mirrors for future hard X-rays microscope applications. [Copyright &y& Elsevier]

Abstract: Nickel/titanium multilayers (ML) and supermirrors (SM) were fabricated by DC magnetron sputtering on glass or Si (100) substrates. It was possible to increase the reflectivity of ML and SM by the deposition of an ultrathin Cr layer at the Ni/Ti interfaces. Interdiffusion decreases when the Ni and Ti are separated by a covering Cr layer (3Å), whereas, in the range where the Cr interlayer thickness is higher than the Ni/Ti interdiffusion depth (approximately 6Å) or the surface roughness, the growth of a closed Cr layer is prohibited reducing the reflectivity. The presence of a 10Å Cr interlayer on some Ti layers also results in enhanced reflectivities due to a smoothing effect of the interface for the following layers. The reflectivities of two monochromators for and a bandwidth (Δλ/λ) of 6% and 12% reach a value of approximately 0.90. [Copyright &y& Elsevier]

We describe the distinction between the operation of a short focal length x-ray microscope forming a real image with a laboratory source (convergent illumination) and with a highly collimated intense beam from a synchrotron light source (Köhler illumination). We demonstrate the distinction with a Kirkpatrick-Baez microscope consisting of short focal length multilayer mirrors operating at an energy of 8 keV. In addition to realizing improvements in the resolution of the optics, the synchrotron radiation microscope is not limited to the usual single magnification at a fixed image plane. Higher magnification images are produced by projection in the limit of geometrical optics with a collimated beam. However, in distinction to the common method of placing the sample behind the optical source of a diverging beam, we describe the situation in which the sample is located in the collimated beam before the optical element. The ultimate limits of this magnification result from diffraction by the specimen and are determined by the sample position relative to the focal point of the optic. We present criteria by which the diffraction is minimized. [ABSTRACT FROM AUTHOR]

InFOCμS is a new generation balloon-borne hard X-ray telescope with focusing optics and spectroscopy. We had a successful 22.5-hour flight from Fort Sumner, NM on September 16,17, 2004. In this paper, we present the performance of the hard X-ray telescope, which consists of a depth-graded platinum/carbon multilayer mirror and a CdZnTe detector. The telescope has an effective area of 49 cm2 at 30 keV, an angular resolution of 2.4 arcmin (HPD), and a field of view of 11 arcmin (FWHM) depending on energies. The CdZnTe detector is configured with a 12 × 12 segmented array of detector pixels. The pixels are 2 mm square, and are placed on 2.1 mm centers. An averaged energy resolution is 4.4 keV at 60 keV and its standard deviation is 0.36 keV over 128 pixels. The detector is surrounded by a 3-cm thick CsI anti coincidence shield to reduce background from particles and photons not incident along the mirror focal direction. The inflight background is 2.9 × 10−4 cts cm−2 sec−1 keV−1 in the 20–50 keV band. [ABSTRACT FROM AUTHOR]

This paper is an overview of the research activities carried out in the past five years at the Institute for Physics of Microstructures RAS and “X-ray” Company towards the manufacture of multilayer mirror systems capable of forming X-ray beams in the subnanometer range of wavelengths. The systems fabrication technology is presented, including techniques for producing supersmooth surfaces of specified shape, methods of graded multilayer structure deposition on such surfaces, and the principles of designing optimal mirror parameters. The characteristics of a quadrelliptical reflector—a novel high light-gathering power four-corner focusing system—are reported. [ABSTRACT FROM AUTHOR]