This PDF file contains the front matter associated with SPIE Proceedings Volume 7360, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

High Harmonic Generation is a well established technique for generating Extreme Ultraviolet radiation. It is a promising technique for both structure and spectroscopic imaging due to both the high flux and coherence of the source, and the existence of multiple absorption edges at the generated wavelengths. To increase the flux, a focussing device can be used. Here we present focussing results for a Mo/Si spherical mirror that has been used in an off-axis arrangement, and give extensive analysis of the resulting astigmatic focus and its consequence on diffractive imaging. The astigmatic beam exists as a vertical and horizontal focus, separated by a circle of least confusion. With the help of a theoretical model we show that the most intense part of the beam is always the second line foci and that the phase at the focus is strongly saddle-shaped. However, this phase distortion cannot explain the significant interference peak splitting that is experimentally observed in our diffraction patterns. Instead we propose that the beam quality is degraded upon reflection from the multilayer mirror and it is this asymmetric phase distortion that causes the diffraction peak splitting.

Triggered by the roadmap of the semiconductor industry, tremendous progress has been achieved in the development of Extreme Ultraviolet (EUV) sources and high-quality EUV optical coatings in recent years, opening up also new fields of applications apart from microlithography, such as metrology, high-resolution microscopy, or surface analysis. The Laser-Laboratorium Göttingen has developed a laser-driven plasma source for generation of soft X-rays in the spectral range 2...20 nm. A Nd:YAG laser (1064 nm, 800 mJ, 6 ns) is focused into a gas-target leading to the formation of a plasma which in turn emits characteristic soft X-ray radiation. Hereby the main focus lies on wavelengths around 13.5 nm ("EUV" - future optical lithography) and the so called water window (2.2 nm...4.4 nm - "XUV") region. Depending on the employed target gas, narrow-band (e.g. O₂ for EUV, N₂ for XUV) as well as broad-band (e.g. Xe for EUV, Ar, Kr for XUV) spectra can be obtained. For focusing a flexible Kirkpatrick-Baez optics was developed, providing broad-band light steering due to grazing-incidence reflection. The carbon-coated mirrors of this device are formed by bent silicon wafer slices allowing continuous tuning to the desired curvatures. As an application of such a setup, results on near-edge X-ray absorption fine structure spectroscopy (NEXAFS) at the carbon K-edge will be presented. The investigated systems range from synthetic polymers (PMMA, PI) over organic substances (humic acids) to biological matter (lipids), delivering unique spectra for each compound. Thus NEXAFS spectroscopy using a table-top XUV source could be established as a highly surface sensitive fingerprint method for chemical analysis.

Due to the short wavelength microscopy with extreme ultraviolet (EUV) light is optimally suited for detecting defects e.g. on mask blanks for EUV lithography. In this work the use of a zone plate lens as a second magnification step in EUV microscopy with a multilayer coated Schwarzschild objective is suggested. The zone plate has to be adapted to the optical system and to have a magnification high enough to match the resolution of the Schwarzschild objective to the detector pixel size. The resulting zone plate should have only a few tens of zones and about 1 μm resolution which reduces fabrication demands. Furthermore, this combination enables a scan and zoom procedure where first the measurements are carried out just with a Schwarzschild objective allowing only a small magnification but larger object field. Then, in areas of interest, the second magnification step is switched on by inserting a zone plate in front of the detector and refocusing the sample. The paper addresses regulations for the zone plate design, simulations of the whole optical system and corresponding demonstration experiments on test structures.

Compound refractive x-ray lens is a unique device to form image of opaque object which is illuminated by x-rays. It is consisted of a lot number of placed in-line concave microlenses and works like ordinary refractive lens for visual light. In contrast to other x-ray optical devices, it could achieve satisfying resolution without complicated equipment. The spherical compound refractive x-ray lens used in this experiment is composed of 123 biconcave microlenses of 200 μm diameter. Each microlens was formed by the epoxy between two bubbles which were injected into an epoxy-filled glass capillary. There are three advantages ensuring good image quality of the lens for using in hard x-rays: (1) The epoxy (C₁₀₀H₂₀₀O₂₀N, 1.08 g/cc) is composed of carbon, hydrogen and nitrogen, each of them is characterized by a low absorption coefficient for 5-30 keV x-rays. (2) Because of the nature of physics forming the bubble, the lens surface quality is extremely good. (3) The capillary makes sure that the series of unit lenses are well aligned coaxially. The lens focal length is 114 mm at 8.05 keV which is adjusted according to thick-lens analysis. X-ray images of grid mesh are compared between using a copper anode x-ray tube without filter and a synchrotron radiation source with monochromator. It could be found that the resolution and contrast are improved a lot by using monochromatic x-rays. The field of view and geometrical distortion around the edges of the field of view are reduced because of using a synchrotron radiation source. For x-ray tube as source the lens achieved a spatial resolution of 5 μm and field of view of about 700 μm. For a synchrotron radiation source, that is 3.8 μm by 2.3 μm resolution and field of view of about 316 μm by 128 μm.

The UK Smart X-Ray Optics consortium is developing novel reflective adaptive/active x-ray optics for small-scale laboratory applications, including studies of radiation-induced damage to biological material. The optics work on the same principle as polycapillaries, using configured arrays of channels etched into thin silicon, such that each x-ray photon reflects at most once off a channel wall. Using two arrays in succession provides two reflections and thus the Abbe sine condition can be approximately satisfied, reducing aberrations. Adaptivity is achieved by flexing one or both arrays using piezo actuation, which can provide further reduction of aberrations as well as controllable focal lengths. Modelling of such arrays for used on an x-ray microprobe, based on a microfocus source with an emitting region approximately 1μm in diameter, shows that a focused flux approximately two orders of magnitude greater than possible with a zone plate of comparable focal length is possible, assuming that the channel wall roughness is less than about 2nm.

The immediate future for X-ray astronomy is the need for high sensitivity, requiring large apertures and collecting areas, the newly combined NASA, ESA and JAXA mission IXO (International X-ray Observatory) is specifically designed to meet this need. However, looking beyond the next decade, there have been calls for an X-ray space telescope that can not only achieve this high sensitivity, but could also boast an angular resolution of 0.1 arc-seconds, a factor of five improvement on the Chandra X-ray Observatory. NASA's proposed Generation-X mission is designed to meet this demand; it has been suggested that the X-ray optics must be active in nature in order to achieve this desired resolution. The Smart X-ray Optics (SXO) project is a UK based consortium looking at the application of active/adaptive optics to both large and small scale devices, intended for astronomical and medical purposes respectively. With Generation-X in mind, an active elliptical prototype has been designed by the SXO consortium to perform point-to-point X-ray focussing, while simultaneously manipulating its optical surface to improve its initial resolution. Following the completion of the large scale SXO prototype, presented is an overview of the production and operation of the prototype, with emphasis on the X-ray environment and preliminary results.

There is a growing need for multiply nested large area X-ray mirrors with very fine angular resolution in future X-ray astrophysics experiments. Despite of promising results of several exploited technologies, it is not demonstrated yet that these technologies will provide the required angular resolutions of order of few arcsec. The alternative approach described in this paper is the method of active X-ray optics. In addition, active approaches based on computer control may be applied directly during manufacturing of advanced X-ray optics elements. We propose these methods as an alternative for the IXO project recently under study by ESA/NASA/JAXA.

We are developing grazing-incidence x-ray optics for high-energy astrophysical applications using the electroformnickel replication process. For space-based applications these optics must be light-weight yet stable, which dictates the use of very-thin-walled full-shell mirrors. Such shells have been fabricated with resolution as good as 11arcsec for hard x-rays, and technology enhancements under development at MSFC are aimed at producing mirrors with resolution better than 10 arcsec. The challenge, however, is to preserve this resolution during mounting and assembly. We present here a status report on a mounting and alignment system currently under development at Marshall Space Flight Center designed to meet this challenge.

We report on our development of hot plastic deformation of silicon wafer for high-resolution and light-weight X-ray optics. The highly polished silicon wafer with an excellent flat surface is a promising candidate for the next generation space X-ray telescopes. Deformation accuracy and stability, especially if elastic deformation is used, are issues. The hot plastic deformation of the silicon wafer allows us 3-dimensional shaping without spring back after the deformation. As a first step of R & D, we conducted the hot plastic deformation of 4-inch silicon (111) wafers with a thickness of 300 μm by using hemispherical dies with a curvature radius of 1000 mm. The deformed wafer kept good surface quality but showed a slightly large curvature of 1030 mm. We measured the X-ray reflectivity of the deformed wafer at Al Kα 1.49 keV. For the first time, we detected the total X-ray reflection on the deformed wafer. Estimated rms surface roughness was 0-1 nm and no significant degradation from the bare silicon wafers was seen.

We have been developing ultra light-weight X-ray optics using MEMS (Micro Electro Mechanical Systems) technologies.We utilized crystal planes after anisotropic wet etching of silicon (110) wafers as X-ray mirrors and succeeded in X-ray reflection and imaging. Since we can etch tiny pores in thin wafers, this type of optics can be the lightest X-ray telescope. However, because the crystal planes are alinged in certain directions, we must approximate ideal optical surfaces with flat planes, which limits angular resolution of the optics on the order of arcmin. In order to overcome this issue, we propose novel X-ray optics based on a combination of five recently developed MEMS technologies, namely silicon dry etching, X-ray LIGA, silicon hydrogen anneal, magnetic fluid assisted polishing and hot plastic deformation of silicon. In this paper, we describe this new method and report on our development of X-ray mirrors fabricated by these technologies and X-ray reflection experiments of two types of MEMS X-ray mirrors made of silicon and nickel. For the first time, X-ray reflections on these mirrors were detected in the angular response measurements. Compared to model calculations, surface roughness of the silicon and nickel mirrors were estimated to be 5 nm and 3 nm, respectively.

The X-ray optics is a key element of various X-ray telescopes, X-ray microscopes, as well as other X-ray imaging instruments. The grazing incidence X-ray lenses represent the important class of X-ray optics. The replication technology represents an important alternative to other methods of X-ray optics production. We report on the past (first replicated Xray mirror has been produced by our group almost 40 years ago), present and future of replication of X-ray optics with emphasis on grazing incidence optics of various types and geometry. The various types of X-ray optics produced by replication with emphasis on astronomical optics are described and summarized. It is shown that the replicated X-ray optics is expected to still play a major role in future space experiments and projects such as the ESA/NASA/JAXA IXO project and other coming space missions.

Analytical and numerical simulations were carried out for both, surface profiles measured on a real ultra precise mirror by use of the BESSY-NOM slope measuring profiler as well as for model local surface distortions. The effect of mirror imperfections could be properly handled in the frame of the wave optics approach. In spite of the large distances, for hard X-rays one still needs to carry out full-scale calculations surpassing the far field approximation. It is shown that the slope errors corresponding to medium spatial frequency components are of a special importance for the properties of coherent beam reflection from ultra smooth mirrors. The typical height errors for this component should not exceed 1-2 nm. Calculations show that reflection on such a mirror surface still imposes substantial wave field distortions at distances of several hundred meters from the mirror relevant for European XFEL beamlines. Requirements and trade-off for high precision mirrors and demands to coherent beams propagations are discussed.

Lobster eye optics, as a wide field of view imaging system, is perfectly suited for x-ray astronomy but can be useful also in the lab. This paper presents a brief overview of the technologies developed in our group, where the glass and silicon mirrors are used to built up the Schmidt lobster eye design and mainly discuss the mirror design consequences on the resulting imaging properties of the system. Corrections of various image distortions and imperfections, either geometric, spectral or temporal in case of scanning observations have to be applied in order to get a valuable instrument. Several image processing methods are discussed and its strengths and weaknesses are shown for both astronomy and laboratory experiments.

The replication technology originally developed for astronomical X-ray optics can be also effectively applied for laboratory mirrors with small apertures, even below few mm. Grazing incidence micromirrors of ellipsoidal or parabolic shape with apertures below 1 mm have numerous potential applications in many areas of applied physics, molecular biology and material research, including synchrotron. One of the most important applications of such optics is in its combination with microfocus X-ray generator. Extremely intense collimated or focused high-quality X-ray beams from tabletop equipment can be obtained in this way. It is shown that though developed primarily for macromolecular crystallography, this combination gave excellent results also in other fields of science and technology. Computer raytracing and experimental data characterizing mirror and X-ray beam parameters in typical applications are also presented.

A dispersive spectrometer onboard the International X-ray Observatory (IXO) provides a method for high throughput and high spectral resolution at X-ray energies below 1 keV. An off-plane reflection grating array maximizes these capabilities. We present here a mature mechanical design that places the grating array on the spacecraft avionics bus 13.5 m away from the focal plane.

The International X-Ray Observatory (IXO) is a NASA, ESA, and JAXA joint mission. It requires a mirror assembly with unprecedented characteristics that cannot be provided by existing optical technologies. In the past several years, the project office at NASA Goddard Space Flight Center has supported a vigorous mirror technology development program. This program includes the fabrication of lightweight mirror segments by slumping commercially available thin glass sheets, the support and mounting of these thin mirror segments for accurate metrology, the mounting and attachment of these mirror segments for the purpose of X-ray tests, and development of methods for aligning and integrating these mirror segments into mirror assemblies. This paper describes our efforts and developments in these areas.

We report on recent progress with development of astronomical X-ray optics based on thermally formed glass foils and on bent Si wafers. Experiments with thermal glass forming have continued adding wider range of evaluated and optimized parameters. Recent efforts with Si wafers have been focused on their quality improvements such as flatness and thickness uniformity in order to better meet the requirements of future X-ray astronomy projects applications, as well as on study of their surface quality, defects analysis, and methods for its reproducible measurement. The role of substrates quality in performance of final mirror arrays, as required by large future space X-ray astronomy experiments was also studied.

A double-periodic multilayer method was proposed to test KBA system of 4.75keV using 8keV source. Alignment of angle is the key for most of grazing incidence systems in x-ray range. But for soft x-ray, strong absorption makes the alignment have to be operated in vacuum, which is difficult enough. A double-periodic multilayer was used to experiment at 8keV in air replacing 4.75keV in vacuum. This multilayer includes two parts, the top and the bottom. The top is W/B₄C multilayer with four bilayers and 6.93nm periods. The bottom is W/B₄C multilayer with 10 bilayers and 3.95nm periods. For 8keV energy, x-ray will penetrate through the top and reflected by the bottom. While for 4.75keV, x-ray will be reflected by the top directly. The full width of half maximum is 0.1° at 8keV and 0.3° at 4.75keV, so it is accurate enough for 4.75keV to experiment at 8keV, which was also verified by the 1-D KBA experiment. This double-periodic multilayer provides a valid solution for alignment in soft x-ray range.

We report measurements of the reflection spectra of (i) concave (spherical and parabolic) Mo/Si, Mg/Si, and Al/Zr multilayer mirrors (MMs) intended for imaging solar spectroscopy in the framework of the TESIS/CORONAS-FOTON Satellite Project and of (ii) an aperiodic Mo/Si MM optimized for maximum uniform reflectivity in the 125-250 Å range intended for laboratory applications. The reflection spectra were measured in the configuration of a transmission grating spectrometer employing the radiation of a tungsten laser-driven plasma as the source. The function of detectors was fulfilled by backside-illuminated CCDs coated with Al or Zr/Si multilayer absorption filters. High-intensity second-order interference reflection peaks at wavelengths of about 160 Å were revealed in the reflection spectra of the 304-Å Mo/Si MMs. By contrast, the second-order reflection peak in the spectra of the new-generation narrow-band (~12 Å FWHM) 304-Å Mg/Si MMs is substantially depressed. Manifestations of the NEXAFS structure of the L_{2, 3} absorption edges of Al and Al₂O₃ were observed in the spectra recorded. The broadband Mo/Si MM was employed as the focusing element of spectrometers in experiments involving (i) the charge exchange of multiply charged ions with the donor atoms of a rare-gas jet; (ii) the spectroscopic characterization of a debris-free soft X-ray radiation source excited by Nd laser pulses in a Xe jet (iii) near-IR-to-soft-X-ray frequency conversion (double Doppler effect) occurring in the retroreflection from the relativistic electron plasma wake wave (flying mirror) driven by a multiterawatt laser in a pulsed helium jet.

We present the characterization of Al/SiC periodic multilayers designed for optical applications. In some samples, a thin layer of W or Mo is added at the SiC-on-Al interfaces. We use x-ray reflectivity (XRR) in order to determine the parameters of the stacks, i.e. thickness and roughness of all the layers. We have performed x-ray emission spectroscopy (XES) to identify the chemical state of the Al and Si atoms present within the structure from an analysis of the shape of the Al Kβ and Si Kβ emission bands. Finally, time of flight secondary ion mass spectrometry (ToF-SIMS) is used to obtain the depth profile of the different elements present within the studied stacks. A fit of the XRR curves shows that the Al/SiC multilayer present large interfacial roughness (up to 2.8 nm), which is decreased considerably (down to 1 nm or less) when the refractory metal layers are introduced in the periodic structure. The combination of XES and ToFSIMS allows us to conclude that in these systems the roughness is a purely geometrical parameter and not related to chemical interfacial reactions.

Periodic multilayers of nanometric period are widely used as optical components for the X-ray and extreme UV (EUV) ranges, in X-ray space telescopes, X-ray microscopes, EUV photolithography or synchrotron beamlines for example. Their optical performances depend on the quality of the interfaces between the various layers: chemical interdiffusion or mechanical roughness shifts the application wavelength and can drastically decrease the reflectance. Since under high thermal charge interdiffusion is known to get enhanced, the study of the thermal stability of such structures is essential to understand how interfacial compounds develop. We have characterized X-ray and EUV siliconcontaining multilayers (Mo/Si, Sc/Si and Mg/SiC) as a function of the annealing temperature (up to 600°C) using two non-destructive methods. X-ray emission from the silicon atoms, describing the Si valence states, is used to determine the chemical nature of the compounds present in the interphases while X-ray reflectivity in the hard and soft X-ray ranges can be related to the optical properties. In the three cases, interfacial metallic (Mo, Sc, Mg) silicides are evidenced and the thickness of the interphase increases with the annealing temperature. For Mo/Si and Sc/Si multilayers, silicides are even present in the as-prepared multilayers. Characteristic parameters of the stacks are determined: composition of the interphases, thickness and roughness of the layers and interphases if any. Finally, we have evidenced the maximum temperature of application of these multilayers to minimize interdiffusion.

A numerical method to design multilayer coating (ML) is presented. The mathematical tool is based on an "evolutive strategy" algorithm which provides aperiodic solutions by maximizing input merit functions. It allows the optimization of any kind of structures, comprising interlayers and capping layers, and modelling also inter-diffusion and interface roughness. It has been applied to the design of MLs for different applications, as photolithography, space instrumentation and short pulse preservation/compression. The optimization allows the control of the standing wave distribution inside the ML. When the EUV radiation interacts with the structure, the superposition of the incident and reflected electromagnetic wave generates a standing wave field distribution in the ML. An aperiodic design allows the regulation of the distribution of this field, attributing specific properties to the ML. An experimental technique to recover standing wave intensity on top of the ML is also cited. The technique is based on electron photoemission measurements, which allow to determine both reflectivity as well as phase on top of ML. Thanks to this technique, both tests of the ML performances compliance with expected theoretical ones and of degradation through time can be carried on.

In recent years telescopes based on near normal-incidence multilayer (ML) technology have been employed in many missions for imaging the Sun at selected EUV wavelengths. Such coatings have not negligible bandwidth, therefore the detected signal often includes the contribution of unwanted adjacent spectral lines. In this work we propose an innovative method for designing suitable ML capping layers able to preserve the reflectivity peak of the underneath structure at the selected wavelength while rejecting the unwanted lines. Theoretical design and experimental results are presented and discussed.

Depth-graded multilayer structures are widely considered as the preferred technology for the next generation of hard Xray telescopes operating in the spectral range up to several tens of keV. This contrasts to earlier generation telescopes which operated in the 1-10 keV range, and utilized single material reflection layers (e.g. Au). Several future space missions are scheduled to include optics comprising up to hundreds of nested shells with Wolter-I profile. Therefore, the need for an industrial strength (in terms of robustness, reliability and precision) manufacturing process for such multilayers has emerged. In this paper, we will discuss the enabling technologies towards "industrial" Physical Vapor Deposition (PVD) technology we have developed for this precision coating process. More specifically, we will review the results obtained on periodic and a-periodic W/Si multilayers, which have been produced on shells of 600 mm height and 300 mm diameter. Points that will be discussed include: · Advanced process control based on in-situ sensors and its effect on repeatability and stability of the process. · Ex-situ metrology methods · Thickness homogeneity over large areas

An auxiliary visible imaging method was introduced to solve the axial and pointing alignment of x-ray Kirkpatrick-Baez optics. Through ZEMAX simulation and x-ray imaging experiments, the axial and pointing alignment accuracy were determined to be ±300μm and ±20μm respectively. The numerical aperture of x-ray Kirkpatrick-Baez optics is rather small, so it's impossible to adjust Kirkpatrick-Baez system by visible imaging directly. An auxiliary visible lens was designed, which was equivalent to x-ray Kirkpatrick-Baez optics on conjugate relationship and accuracy control. The comparative experiments of visible imaging and x-ray imaging indicate that this auxiliary system could meet the alignment accuracy of Kirkpatrick-Baez optics.

Silicon carbide (SiC) is an attractive material for EUV and soft X-ray optics. CVD-deposited silicon carbide (deposited at 1400° C on Si substrate) is the best reflective material in the whole EUV interval (with about the 48% of reflectance at 121.6 nm). Despite of this, SiC thin films deposited with PVD techniques, such as magnetron sputtering, on silicon substrate, do not have the same performances and they undergo to a degradation with time, probably because of some stoichiometry reason (carbon rich). Depositing stable SiC with PVD techniques is crucial in building ML's, like Si/SiC and SiC/Mg for soft X-ray applications (such space telescope and photolithography). We deposited some preliminary samples using the Pulsed Laser Deposition (PLD) and the Pulsed Electron Deposition (PED) techniques achieving a good reflectance in the whole EUV range (27% at near normal incidence at 121.6 nn) on a silicon substrate. The higher energy involved in these deposition processes could lead to a film with a stoichiometry much closer to the target one. The reflectivity of the deposited films has been measured at the BEAR beamline of the ELETTRA synchrotron in Trieste (Italy) and the optical constants retrieved at six wavelength from 121.6 nm down to 5 nm.

The development of Fourier Transform (FT) spectral techniques in the soft X-ray (100eV to 500eV spectral region) has been advocated in the past as a possible route to constructing a bench-top size spectral imager with high spatial and spectral resolution. The crux of the imager is the soft X-ray interferometer. The auxiliary subsystems include a soft X-ray source, focusing optics and a CCD-based detection system. When tuned over a sufficiently large range of path delays (frames), the interferometer will sinusoidally modulate a spectrum of a wide-band X-ray source centered at the core wavelength of interest with high resolving power. The spectrum illuminates a target, the reflected signal is imaged onto a CCD, and data acquired for different frames is converted to spectra in software by using FT methods similar to those used in IR spectrometry, producing spectral image per each pixel. The use of short wavelengths results in dramatic increase in imaging resolution over that for IR. Important for future NASA missions, and unlike X-ray Absorption Near Edge Structure (XANES) that uses intense and in monochromatic beams which only a synchrotron can deliver, FTXR plans to use a miniature, wide bandwidth X-ray source. By modulating the beam spectrum around the wavelength of interest, the beam energy is used much more efficiently than with gratings (when only a very small, monochromatized portion of the radiation is used at one time) facilitating construction of a bench-top instrument. With the predicted <0.1eV spectral and <100 nm spatial resolution, the imager would be able to map a core-level shift spectrum for each pixel of the image for elements such as C, Si, Ca, N (Kα-lines) which can be used as a chemical compound fingerprint and for imaging intracellular structures. For heavy elements it could provide "bonding maps" (L and M-shell lines), enabling to study fossils of microorganisms on space missions and in returned samples to Earth. We have initiated development of a Fourier Transform X-ray Reflection (FTXR) spectral imager based on the use of a Mach-Zender type interferometer. The enabling technology for the interferometer is the X-ray beam splitting mirrors. The mirrors are not available commercially; multi layers of quarter-wave films are not suitable, requiring a different approach to beam-splitters than in the visible or IR regions. Several efforts by other researchers used parallel slits or stripes for partial transmission, with only a very limited success. In contrast, our beam splitters are based on thin (about 200 nm) SiN membranes perforated with a large number of very small holes, prepared using state-of-art microfabrication techniques that have only recently become available in our laboratory at JPL. Precise control of surface roughness and high planarity are needed to achieve the wave coherency required for high-contrast fringe forming. The perforation design is expected to result in much greater surface flatness, facilitating greater wave coherence than for the other techniques. We report on our progress in the fabrication of beam splitting mirrors to-date, interferometer design, modeling, assembly, and experimental results.

We have developed a generic X-ray tracing toolbox based on Geant4, a generic simulation toolkit. By leveraging the facilities available on Geant4, we are able to design and analyze complex X-ray optical systems. In this article we describe our toolbox, and describe how it is being applied to support the development of silicon pore optics for IXO.

For the purpose of the wavefront profile measurement of XUV beams emitting at 21.2 nm and 30 nm, we designed the PDI (Point Diffraction Interferometer) wavefront sensor. PDI is a self-referencing monolithic device consisting of a thin neutral filter and a very small pinhole located near the axis of the XUV beam focal spot. The small pinhole works as a diffraction aperture generating a reference spherical wave, and working as well as a spatial filter. The material of the thin foil is partially transparent for the XUV radiation, and it determines the visibility of the interference fringes. The interference pattern is recorded by an XUV detector placed behind the foil. From the information encoded in the pattern it is possible sequentially to reconstruct the beam wavefront profile. We will discuss the design and optimization of the PDI wavefront sensor setup.

Two experimental modules of small X-ray telescopes based on the Lobster eye X-ray optics are presented. These modules are regarded to use for x-ray astronomy applications in space. At this time, the optical tests of these modules have been performed. Results of these tests are presented.

In recent years, X-ray telescopes have been shrinking in both size and weight to reduce cost and volume on space flight missions. Current designs focus on the use of MEMS technologies to fabricate ultra-lightweight and high-resolution X-ray optics. In 2006, Ezoe et al. introduced micro-pore X-ray optics fabricated using anisotropic wet etching of silicon (110) wafers. These optics, though extremely lightweight (completed telescope weight 1 kg or less for an effective area of 1000 cm²), had limited angular resolution, as the reflecting surfaces were flat crystal planes. To achieve higher angular resolution, curved reflecting surfaces should be used. Both silicon dry etching and X-ray LIGA were used to create X-ray optics with curvilinear micro-pores; however, the resulting surface roughness of the curved micro-pore sidewalls did not meet X-ray reflection criteria of 10 nm rms in a 10 μm² area. This indicated the need for a precision polishing process. This paper describes the development of an ultra-precision polishing process employing an alternating magnetic field assisted finishing process to polish the micro-pore side walls to a mirror finish (< 4 nmrms). The processing principle is presented, and a polishing machine is designed and fabricated to explore the feasibility of this polishing process as a possible method for processing MEMS X-ray optics to meet X-ray reflection specifications.

We present the design of a high resolution X-ray spectrometer for space based X-ray studies. This novel design utilizes a Kirkpatrick-Baez geometry with an off-plane grating as the secondary optic. This design has been proposed to NASA for flight onboard a suborbital rocket. The approach is low cost, low risk and has applications for future orbital missions.

The Smart X-ray Optics (SXO) programme is developing advanced active-adaptive optics for X-rays. There are two main themes: large optics for applications in astronomy and small scale optics for micro-probing of biological cells and tissue samples using Ti or Cr K_α radiation (4.5keV and 5.4keV, respectively) in studies related to radiation induced cancers. For the latter objective, microstructured optical arrays (MOAs) have been proposed. These consist of an array of channels deep etched in silicon. They use grazing incidence reflection to focus the X-rays through consecutive aligned arrays of channels, ideally reflecting once off a channel wall in each array. Bending the arrays allows variable focal length. The adaptivity is achieved by flexing the arrays using PZT (Lead Zirconate Titanate)-based piezo actuators. The array bending has been modelled using finite element analysis (FEA) and the results showed that for reasonable efficiency, the wall roughness of the channels should not exceed 2nm. This paper describes two techniques of fabrication the MOAs: dry etching and wet etching. The first method requires a special equipment called "inductively coupled plasma" (ICP) using Bosch processes that are designed to produce features with a high aspect ratio with vertical walls. The second method involves using an alkaline solution for etching <110> silicon wafers. This type of wafer was selected because of the large wet etch ratio between the (111) and (100) planes that leads to smooth vertical walls. For our application tetra-methyl-ammonium hydroxide (TMAH) was used as it is fully compatible with CMOS integrated circuit processes.

Future space X-ray astronomy and astrophysics projects require accurate but light and high throughput multiple nested X-ray optics. The Czech Republic started being the full member of ESA in November, 2008 and the participant in the innovative technology developments for the new space mission represents the natural continuation of the efforts of the Czech team in development of innovative X-ray telescopes, focusing on particular demands and requirements of a concrete project, with emphasis on fully new and light-weight technologies. We will report not only on silicon or glass but also on other alternative materials such as SiC or glossy carbon, which could be considered as suitable materials for the producing of precise light weight X-ray optics due to their physical and chemical properties.

A laboratory system with a crystal concentrator for focusing γ-rays has been developed. The facility has been designed in particular for tests of diffraction systems based on small crystals in the Bragg and Laue configurations. Two radioactive sources (Co-57 and Ba-133) are being used to cover the energy range from 30 to 400 keV. The diffracted beam is detected using Germanium (HPGe) and CdZnTe detectors. We report on the preliminary characterization of crystal mosaicities for different crystals.