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We have developed a submicron-area high energy resolution photoelectron spectroscopy system equipped with a multilayer-coated Schwarzschild objective for forming a soft x-ray microbeam. We show the photoelectron microspectroscopy results of the cross section of a semiconductor double heterostructure sample, namely an epitaxial film [InP (50 nm thick)/ In0.53Ga0.47As (2.3 μm thick)/InP (100) substrate] grown by metalorganic chemical vapor deposition. The core-level photoelectron spectra were obtained from the cross section of the cleaved sample. The As 3d, Ga 3d, and In 4d peaks were observed in the In0.53Ga0.47As region. In the InP region, the As 3d and Ga 3d peaks were not observed, and only the In 4d peak was. This result corresponds to the structure observed by cross-sectional scanning electron microscopy. Moreover, we observed an irradiation effect that was caused by the microbeam. These results suggest that this photoelectron microspectroscopy system is a powerful tool for studying chemical and electronic states of submicron-area surfaces.

We developed a laboratory used laser-produced plasma X-ray source. Its characteristics concerning X-ray radiation were evaluated for Al, Ti, Fe and Nb targets in a wavelength region from 2 to 18 nm. The experimental results shows that the source has a brightness of 108∼109 photons/0.1 nm/rad2/mm2/shot at a laser intensity of 9×1012 W/cm2 and X-ray radiates with an energy conversion efficiency of about 4%. Futhermore, to demonstrate an application of the source to surface analysis, we constructed an X-ray diffractometer using the source and obtained X-ray diffraction profiles of a periodic Mo/Si multilayer structure.

A soft X-ray microscope with zone plates was set up at UVSOR [synchrotron radiation facility (750MeV, 200mA) at Institute for Molecular Science, Okazaki, Japan]. A 50nm line & space pattern could be resolved at λ=3.2nm. With an environmental chamber (wet cell) using SiN windows, wet biological specimens, such as letus protoplasts, rabbit myofibrils, tubulin of COS cell and Deinococcus radiodurans strains, could be observed at λ=2.5nm. In the present microscope, the numerical aperture of the condenser was much smaller than that of the objective. To adjust both the numerical apertures, an ellipsoidal condenser mirror system was tested, and preliminary result (an image of Cu mesh, 12.7μm pitch) was obtained.

We fabricated a Schwarzschild X-ray objective which has the maximum X-ray transmittance of 9% at the wavelength of 14.1nm and evaluated an X-ray microbeam formed by the objective. We measured the knife-edge response of the microbeam and performed a fitting calculation of the response, using the point-spread function for the objective. It was found that the beam diameter of the microbeam was 45nm. In this paper, details of these experiments and the application of the microbeam will be discussed.

The imaging properties of the soft-X-ray microscopes composed of a Schwarzschild objective and a grazing incidence mirror condenser are discussed. Fundamental formulae on the partially coherent transfer function, the resolution of a two-point object and the edge response have been derived by consideration of the optical properties of an object in soft-X-ray regions. Then these imaging properties for the microscopes are investigated with the formulae and compared with those for a normal circular pupil system.

Proposed is an imaging type Schwarzschild soft X-ray microscope including a condenser optimized for better imaging properties on the basis of Hopkins's theory. The condenser using grazing incidence reflective optics is found most suitable for a Schwarzschild objective. The modulation transfer function (MTF) for the microscope is calculated and it is shown that the MTF is improved with the light intensity distribution on the condenser pupil.

Ayu Plecoglossus altivelis of 12cm in body length were raised in concrete tanks at four different water velocities (4cm/s, 25cm/s, 35cm/s, and 45cm/s) for 60 days. Rearing of the fish in water velocities 35 and 45cm/s exerted favorable growth and feed efficiency. Rearing in current water, however, failed to depress lipid content of muscle, liver, and intraperitoneal fat body when com-pared to that in the standing water (4cm/s). Following the feeding experiment, the fish were starved for 13 days in indoor tanks. The body weight loss was suppressed in the fish reared in water velocities of 35 and 45cm/s. Rearing in high water velocity (

The effects of supplementation of dietary medium chain triglycerides (MCT) at different levels (0, 2, 4, 5, and 6%) to the commercial diet on the quality of Ayu Plecoglossus altivelis were evaluated morphometrically and biochemically. The supplementation of MCT was effective to accelerate body weight grain and to suppress lipid accumulation in the body. Body weight and muscle mass increased and the intraperitoneal fat body, hepatosomatic index, and viscerosomatic index decreased gradually with the increasing level of MCT. The highest weight gain and the lowest lipid accumulation were observed in the 6% MCT sup-plemented group. Supplementation level of 6% or more would be available for the im-provement of growth without deposition of lipid in the body. The view that MCT can used to improve the quality of fish has been further strengthened.

Features and applications of the laser scanning microscope are described, focusing on confocal imaging, the image contrast enhancement effect and three-dimensional surface profile measurement. A longitudinal resolution of 0·01 μm is obtained using a surface profilometer with a position-sensitive detector.

Using the compact SR-ring `AURORA,' imaging performance of the soft x-ray microscope with a Schwarzschild objective were evaluated. The multilayer mirrors of the objective were designed at a wavelength of 135 angstroms with 41 layers of Mo/Si. X rays from the source were filtered with a Be membrane (1.5 micrometers thickness), and then focused on a sample with a paraboloidal condenser. Visible and UV light was removed with the Be filter, and hard x ray was removed with the condenser. X rays transmitted through the sample were imaged on a detector (micro-channel plate) with the Schwarzschild objective. The image was converted to visible light by a fluorescent screen, and monitored with a CCD camera. Magnified ratio was 200. Spatial resolution was evaluated as 0.3 - 0.45 micrometers from an edge response.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The design of the Schwarzschild objective considering an alignment error is discussed and its fabrication for a soft x-ray microscope is described. It is shown that performance degradation of a Schwarzschild objective by an alignment error can be reduced in a heterocentric system, in which the center of a curvature of a concave mirror is not coincident with that of a convex mirror. Objectives with a magnification of 100 and 224 have been fabricated. To complete an indispensable and difficult alignment within the objective itself, the two mirrors are mounted together in the same frame. The alignment errors of the mirrors are detected and their positions are corrected in a newly developed alignment system, which allows the alignment to achieve the tolerance of 0.3 micrometers . The fabrication of Mo/Si multilayers used for the mirrors are also described briefly. A reflectometer using a laser produced plasma source has been developed to measure reflectances of multilayers. The Mo/Si multilayer deposited by magnetron sputtering shows a reflectance over 40% at a wavelength of roughly 135 angstroms.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A soft X-ray microbeam was formed using a Schwarzschild X-ray objective designed to have transmittance at a wavelength of 14 nm. The widths of the X-ray beam on and off the focal plane were measured using a knife-edge method, and it was found that the size of the X-ray microbeam was 70 nm on the focal plane. We obtained X-ray transmission images of a silicon etching pattern and demonstrated that an image at a spatial resolution of better than 100 nm was obtained using the microbeam. We also discuss practical applicability of the microbeam.

We fabricated a Schwarzschild x-ray objective with 224 magnification and a theoretical spatial resolution of 25 nm at a wavelength of 13.5 nm. We measured its knife-edge responses. To determine its spatial resolution, we performed a fitting calculation of the knife-edge response, using the point-spread function for an annular pupil; it was found that the objective has a spatial resolution of 35 nm at the focal point.

The resolution of optical systems with annular pupil objectives is discussed, particularly with respect to the imaging properties of soft-x-ray imaging optical systems. Images of two dark bars in a bright field and knife-edge responses, which are calculated with partially coherent transfer functions, were used to estimate the resolution. Resolution for two bright points in a dark field, which is conventionally used in Rayleigh’s analysis, is also discussed for comparison. It was found that annular systems with obstruction ratios of more than 0.6 show resolution properties different from those of systems with low-obstruction-ratios. The high-obstruction-ratio systems show lower resolution for the two-dark-bar objects and higher resolution for the two-bright-point objects, whereas the low-obstruction-ratio systems show almost the same resolution for both objects.

A compact soft x-ray reflectometer usable in a small laboratory is developed for measurement of the soft x-ray reflectance of a multilayer mirror in a wide wavelength range, i.e. , including the water window (23 to 44A). In this reflectometer, the reflectance can be measured as a function of wavelength or incidence angle. A laser-produced plasma soft x-ray source, which is small but has high brightness, makes it possible to construct the compact soft x-ray reflectometer. The soft x rays generated by the source are monochromatized with a grazing incidence reflection grating. Incidence angle dependency of the reflectance can be measured from 2 deg (almost normal incidence) to 85 deg. Reflectances of a Ni/Ti multilayer and a Mo/Si multilayer are measured, and 10.9% at a wavelength of 40.8A and an angle of 75.1 deg and 38% at a wavelength of 135.5A and an angle of 25.7 deg from normal incidence are obtained, respectively.

The spatial resolution of a Schwarzschild objective was evaluated at the wavelength of 135 Å by means of an apparatus constructed using the knife-edge method which is suitable to the measurement of higher resolution. The knife-edge response of the objective was measured with the apparatus. Then the results were compared with the theoretical responses calculated using ray tracing. It is found that the measured responses of the objective are almost the same as the theoretical ones. We conclude that the objective has the spatial resolution of 0.2 µm.

A real-times canning laser microscope for biological research is described, in which an acoust-optical deflector using TeO2 is used to observe the specimens in real time. The resolving power is 0.19μm when a He-Cd laser is used. High contrast clear images of nondyed bacilli or cells are obtained. Minute structures of a human chromosome which are hardly recognizable with a conventional optical microscope are clearly obserbed.

SUMMARY A beam-deflection type laser scanning microscope for differential phase contrast images using the split-detector technique is developed and the images are obtained in real time (30 images/s). The special optical design allows transfer of the pupil information necessary to the imaging of the differential phase contrast images during beam deflection and the use of acousto-optic deflectors with the associated correction system enables real time imaging. Differential phase images of surface details of crystals are simply obtained without silver coating or etching, which are indispensable in a normal DIC. Biological specimens are also observed.

A scanning laser microscope for biological research is described, in which an acoustooptical deflector is used to observe the specimens in real time. High-contrast clear images of nondyed bacilli are obtained. A minute structure of a human chromosome which is hardly recognizable with a conventional optical microscope is clearly obtained.

The throughput of a Schwarzschild objective using undulator synchrotron radiation was measured. Conventionally, the throughput was estimated from the squared reflectivity of one multilayer mirror and from the obstruction ratio. However, we evaluated the transmission ratio from the input and output photon flux using a precisely calibrated monochromatic beam from an undulator light source. It was found that the objective has a maximum throughput of 8.5% at a wavelength of 13.9 nm.

A submicrometre-area photoelectron spectroscopy system that uses a multi-layer-coated Schwarzschild objective as the soft X-ray microbeam optics has been developed. The system is located at an undulator beamline (BL-16U) at the Photon Factory in the High Energy Accelerator Research Organization. By knife-edge measurement, the microbeam size was estimated to be 160 nm at the sample position using a 25–75% criterion. Photoelectron spectral measurements revealed that the Fermi edge width was 0.12 eV, which means that the instrumental resolution was 0.05 eV, after removing the natural broadening of the Fermi edge at room temperature. This system offers both high energy resolution and high spatial resolution.