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We have developed an objective soft x-ray flat-field spectrograph installed in electron microscopes (EMs). The spectrograph has two attractive features. One is that it is designed to cover a wide energy range of 50-4000 eV by using four varied-line-spacing holographic gratings (VLSHGs) optimized for 50–200 eV, 155–350 eV, 300–2200 eV, and 2000–4000 eV. The gratings dedicated for the respective energy ranges can be accommodated in the single spectrograph. This advantage comes from that the positions of the source points and image planes are assumed as the common parameters in the design of all gratings. Therefore, it allows to easily change the energy range by only choosing an appropriate grating and its position. The other is the application of a newly invented W/B4C multilayer coating. It has been adopted to the grating for the 2000–4000 eV range to overcome the considerable decrease of the diffraction efficiency in the energy range above ~2 keV. The novel coating makes it possible to enhance uniformly the diffraction efficiency at a constant incidence angle in the whole energy range.

A versatile soft x-ray flat-field grating spectrograph to be installed to a conventional transmission electron microscope has been developed. A holographic spherical grating of a 1200-lines/mm effective groove density which places emphasis on the low energy region of 50-200 eV is designed by an aspheric wavefront recording system. Laminar and blazed types master (LM and BM) gratings and their respective replica (LR and BR) gratings are fabricated by holographic exposure and ion-beam etching methods. Absolute diffraction efficiencies in the 50-300 eV range at the angle of incidence of 86.0 degrees were measured using a synchrotron radiation. The first order diffraction efficiencies are 6.1-7.5% (or 12%) for LM (or BM) and 7.4-9.6% (or 13%) for LR (or BR) gratings at near 55 eV, and over 5% (or 8%) in the 50-200 eV range for LM and LR (or BM and BR) gratings. The replica gratings show the comparable first-order diffraction efficiencies with their respective laminar and blazed types of master gratings.

This paper gives an overview of recent progress of laser-driven plasma x-ray lasers in Japan Atomic Energy Agency (JAEA). Fully spatial coherent plasma x-ray laser (XRL) at 13.9 nm with 0.1 Hz repetition rate has been developed using new driver laser system TOPAZ, and the succeeding optimization of the pumping condition has realized more efficient generation of the coherent x-ray pulse. The 0.1 Hz XRL is now routinely used in the wide variety of the application experiments: The highlights of these applications are the study of fluctuation in the atomic structure of ferroelectric substances under the phase transition using the double XRL probe beam technique and the construction of new x-ray laser interferometer to observe nano-scale dynamics of materials.

A new type of monochromators that incorporates two kinds of Monk-Gillieson monochromators has been designed and constructed for the purpose of realizing an evaluation beamline for characterizing soft X-ray optical elements in a wide wavelength range of 0.7-25 nm. One of the monochromators is a conventional type equipped with three varied-line-spacing plane gratings, allowing a choice of two inclusion angles. The other is a new type that employs a scanning mechanism based on Surface Normal Rotation (SNR). The SNR scheme provides high throughput at short wavelengths and simple scanning mechanism by means of a grating rotation about its normal. The monochromators is operated in the SNR and conventional modes over the ranges of 0.7-2.0 nm and 2.0-25 nm, respectively. The system was installed on a beamline of the AURORA, a superconducting compact storage ring, at the Synchrotron Radiation Center, Ritsumeikan University. In this paper we describe the optical and mechanical designs of the monochromators, and a practical method of wavelength calibration. Also experimental data are shown which demonstrate the performance and versatility of the new type of Monk-Gillieson monochromators.

An aspheric wave-front recording system was designed to produce a holographic grating for use in a standard soft X- ray flat field spectrograph interchangeable with a mechanically ruled varied-line-spacing (VLS) grating. The grating grooves recorded with the designed aspheric wave- front recording system were processed to form a laminar groove profile by means of reactive ion etching. Measurements done with synchrotron radiation and a laboratory X-ray source are reported for this laminar-type grating and a commercial grating replicated from a mechanically ruled VLS grating that was specifically designed and fabricated for the standard soft X-ray flat- field spectrography. The laminar-type holographic grating is found to have an absolute first-order efficiency of approximately 10% for wavelengths of approximately 4.5 - 12 nm. It is also shown that the holographic grating is effective in suppressing the higher orders and stray-light level for soft X-ray of 4.36 nm (C-K) and has a comparable spectral resolution to the replica VLS grating.

A design method, called the hybrid design method, is applied to the design of(1) a zero-dispersion and constant-devialion type doub1egrating predisperser system for a VUV high-resolulion off-plane Eagle spectrometer which utilizes a high-order spectrum and (2) a wide-aperture Wadsworth4ype VtJV imagng spectrograph which consists of aspheric mirror and grating. The gralings of these systems are holographic gralings recorded with aspheric wave fronts. The results Obtained show the effectiveness of the hybrid design method and the versatile applicability ofa holographic grating recorded with asphenc wave fronts.

Efficiency, scattering, and spectral resolution measurements were made on two equivalent varied-line-spacing plane (VLS) gratings with a central groove density of 1200 1/mm, one a blazed grating made by mechanical ruling and the other holographically recorded and ion etched to a laminar groove profile. The line spacing variation of the holographic grating was obtained by interfering a plane wave and a spherical wave. Both gratings were designed to be used in the monochromator of the Calibration and Standards beamline built and operated by the Center for X-ray Optics at the Advanced Light Source, and all measurements were made efficient in the 600-850 eV region but more efficient below 600 eV and above 850 eV. Substitution of the holographic grating into the beamline extended the energy range from 1000 eV to 1300 eV. The holographic grating exhibited considerably less scattering, but its spectral resolution was lower at an energy of 400 eV. It is likely that this resolution can be improved by adopting a holographic recording system which employs interference of a plane and an aspheric wave.

Manufacturing for large-scaled integrated circuit requires a large exposure area and high throughput. According to the SIA road map, 16 Gbit DRAM requires exposure area of 26 mm X 44 mm for a 0.1-micrometers generation. In order to determine these feasibility, we designed at imaging optics which is based on three aspherical-mirror optics for EUVL. This designed optics is a very compact one, and the optics can achieve a resolution of less than 0.1 micrometers and an ring field of 26 mm X 1.0 mm on a wafer. In assembling the demagnifying optical system, various adjustment errors such as decenter, tilt and despace affect one another in an intricate way and degrade the system performance in a complicated manner. It is therefore important in practice to adjust the system as a whole rather than trying to optimize the effects of individual adjustment mirrors on the resolution by fulfilling respective tolerances. Another important factor affecting the system performance is surface figure error of aspherical mirrors. The surface figure error of aspherical mirror is estimated by calculation of ray tracing method. We obtained the tolerance of the figure errors of M1, M2, and M3 to be 0.66 nm, 0.75 nm, and 0.90 nm for replicating 0.1-(mu) nm-pattern, respectively. It is found that these values are twice or three times larger than the values obtained from Marechal criteria.

A step-and-scan type scanning scheme has been investigated for the purpose of simplifying the high-precision scanning mechanism adopted in the 6.65-m off-plane Eagle type monochromator on an undulator beamline of the Advanced Light Source at Lawrence Berkeley National Laboratory. In this scheme it is proposed to scan over a wavelength range of 80 - 180 nm by covering a range of 0.99 (lambda) t - 1.01 (lambda) t at a time by simply rotating the grating fixed at the position for a wavelength (lambda) t to which the undulator is tuned. When the undulator is tuned to another (lambda) t, the grating is translated to a new fixed position and scanning is made by simple grating rotation. A ruled grating with varied line spacing and straight grooves and a holographic grating recorded with spherical wave- fronts were designed to match the proposed scanning scheme and to meet the required energy resolution of approximately 1.0 cm-1 over the entire scanning range. The results of ray tracing show that the designed gratings with 2400 grooves/mm and 6.1-m radius of curvature would provide a resolution of

A long undulator installed at a low emittance storage ring, generates quasi-monochromatic beams of high brightness and partial coherence properties; however, this also raises concerns regarding high heat loads on beam line components. There have been intensive research efforts to develop beam line optics to exploit brightness and coherence properties from undulators. These components must withstand high heat loads produced by intense synchrotron radiation beams impinging on their surface which could degrade beam line performance. The effects of high flux undulator radiation on beam line optics for EUV interferometry and photoemission microscopy will be discussed. Specifically, beam line schematics, design considerations of indirectly side cooled mirror and grating assemblies developed at the Center for X- Ray Optics and recent data of performance under undulator radiation load from beam line BL12.0 being commissioned at the ALS will be presented in this study.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new simulation method has been developed for evaluating the performance of soft x-ray optics for synchrotron radiation (SR) and for estimating tolerances for the fabrication and assembly errors of optics. The method is based on ray tracing and takes into account the surface figure error, thermal deformation, and SR source parameters. The method is applicable to aspheric mirrors and gratings with or without varied spacing and curved grooves. To evaluate the method, we applied it to the following two optical systems: (1) a Monk- Gillieson type monochromator on an undulator beamline of a third-generation SR source and (2) an extreme ultraviolet projection lithography system for SR from a superconducting compact electron storage ring. The results indicate that the method seems to provide realistic tolerances for the figure error (due to both polishing and heat load) and evaluation of the system performance, though more experimental data are needed to establish the validity of the method.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new simulation method has been developed for evaluating the performance of a monochromator whose grating is exposed to intense undulator radiation. Analytic expressions for the thermally deformed surface figure and distorted groove pattern of the grating are determined first by a finite element method and then they are incorporated into a ray tracing procedure. The method is applied to a simple beamline optics consisting of a U3.9 undulator of the Advanced Light Source and a water-cooled metal grating to see whether this objective monochromator can stand for heat load without degrading its designed performance. The results show that the simulation method is capable of evaluating the performance of a thermally distorted grating and that the heat load would not cause any significant degradation in the spectral resolution and throughput.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An x-ray microscopy resource center for biological x-ray imaging will be built at the Advanced Light Source (ALS) in Berkeley, California. The unique high brightness of the ALS allows short exposure times and high image quality. Two microscopes, an x-ray microscope (XM) and a scanning x-ray microscope (SXM) are planned. These microscopes serve complementary needs. The XM gives images in parallel at comparable short exposure times, and the SXM is optimized for low radiation doses applied to the sample. The microscopes extend visible light microcopy toward significantly higher resolution and permit images of objects in an aqueous medium. High resolution is accomplished by the use of Fresnel zone plates. Design considerations to serve the needs of biological x-ray microscopy are given. Also the preliminary design of the microscopes is presented. Multiple wavelength and multiple view images will provide elemental contrast and some degree of 3-D information.