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An X-ray microbeam with a small angular divergence and a narrow energy bandwidth has been produced at BL24XU at SPring-8. The beam size was measured to be 3.1 microm and 1.6 microm in the horizontal and vertical directions, respectively, and the horizontal angular divergence was 4.0 arcsec. Using this microbeam the crystallinity estimation of thin layers on silicon-on-insulator (SOI) wafers is demonstrated. In reciprocal-space maps the lattice tilt variations were 80 arcsec and more than 220 arcsec in the SOI layers on bonded and SIMOX wafers, respectively. In equi-tilt maps, the typical equi-tilt areas of the SOI layers were 7 microm and 4 microm in size on the bonded and SIMOX wafers, respectively.

Lattice strain distribution in a silicon substrate covered by an aluminum conductor film has been investigated by a highly parallel X-ray microbeam combined with synchrotron radiation. To evaluate a very local and minute strain in the silicon substrate, intensity maps drawn from a series of rocking curves and reciprocal space intensity maps using an analyzer crystal were obtained using the X-ray microbeam. The results revealed that the deposition of the aluminum layer gave rise to nonuniform strain distribution in the silicon substrate through the silicon oxide layer and that the local strain in the silicon substrate beneath the aluminum film was mainly related to the lattice tilt variation. An intensity map of the rocking curves also revealed the large tilt of the lattice plane in the vicinity of the edge of the aluminum pad.

A new type of high voltage generator has been designed, with the aim of developing a compact, inexpensive and easily-maintained generator for energetic ion beam analyses. It has a similar structure to a rotating disk-type generator, such as the Disktron, and has the potential to have a compact size and satisfactory generating voltage stability. Its generating mechanism is, however, rather similar to rectifier type generators, such as the Cockcroft-Walton and the Schenkel types, so that there are no friction components which might produce a lot of dust, so opening the high pressure tank for cleaning is an infrequent operation. The proposed generator can be produced relatively inexpensively. A single module model has been built and it was confirmed that the proposed generating mechanism functions successfully.

A new compact wavelength-dispersive X-ray spectrometer has been developed for our compact high energy ion microprobe system (“mikro-i”). This spectrometer is designed to detect four light elements, boron, carbon, nitrogen and oxygen. Using two multilayer X-ray analyzers, multilayer benders cut from a single metal block and a gas-proportional counter with a 150 mm × 20 mm wide, 1 μm thick polymer window, the compact dimensions of the spectrometer are achieved. The result of initial X-ray detection has shown that the spectrometer has less than 21 eV (FWHM) resolution for each element, small enough to discriminate their characteristic X-ray lines from disturbing ones. Also, the same detection limit has been shown for oxygen for the trace element analysis.

A compact nuclear microprobe system with a new configuration and a number of analysis functions has been developed. The overall size of the system is 4.5 (length) × 2.5 (width) × 1.8 (height) m. To estimate the focusing performance, secondary electron microscopic (SEM) images of line and 2-dimensional patterns of Au on a Si substrate were obtained. Stripes of 0.75 and 1 μm were resolved in horizontal and vertical directions, respectively. Micro-PIXE has been applied to the analysis of Ti castings. Two kinds of casting samples were prepared. They were cast by using a phosphate bonded or an ethylsilicate bonded investment. It was found that Si and P in the former casting diffuse down to at least 160 and 80 μm under the surface and Si in the latter down to at least 40 μm. It was also found that these values of diffusion depths are in good correlation with the results of a micro-Vicker's hardness test.

We measure the diffraction peaks of InGaAsP selective metal-organic vapor-phase epitaxial layers on 1.7-μm-wide InP stripe regions between a pair of SiO2 mask stripes. This is achieved by using an x-ray microbeam with low angular divergence and a narrow energy bandwidth that was produced through two-dimensional condensation of undulator radiation x rays from a synchrotron light source using successive asymmetric diffraction. The lattice strain is investigated by changing the SiO2 mask width from 4 to 40 μm. The rocking curves reveal clear peak shifts in the InGaAsP layers from the higher angle side to the lower angle side of the InP substrate peaks as the mask width increases.

A collimated line beam is incident at an oblique incident angle of 0.61 rad into an inner surface of a hydrodynamic bearing whose inner diameter and length are 3 mm and 3.5 mm, respectively. Lights reflected in specified directions from the inner surface are selected to obtain an optical field whose phase distribution is proportional to the inner surface profile. This optical field interferes with a reference optical field in a two-wavelength interferometer using a tunable external cavity laser diode. Shapes of grooves with depth of about 5 μm and width of about 0.15 mm formed on the inner surface can be measured with an error less than 0.3 μm., Optical inspection and metrology for non-optics industries : 3-4 August 2009 : San Diego, California, United States. : Aug 2009, San Diego, CA.

Phase-contrast x-ray microscopy has been performed using a point focus x-ray source. The method is essentially the projection microscopy, but the contrast enhancement due to the refraction is obtained by taking a certain sample-detector distance large enough to spatially resolve phase gradients in the x-ray beam. The spatial resolution was measured to be 2.5 μm in horizontal and 2.2 μm in vertical directions. A phase contrast image of a glass tube was taken, and the contrast enhancement was clearly observed in boundary regions. The phase contrast images of a butterfly and a mosquito were also taken. It was confirmed that this method was useful to observe samples composed of light elements such as insects.

A phase zone plate made of tantalum has been designed and fabricated for focusing hard x-rays. It is designed to optically match to the undulator radiation of the BL24XU at the SPring-8. Its focusing properties were measured. The focused beam size smaller than 1 μm was obtained at the photon energy of 10 keV. The diffraction efficiency was measured around 10 keV and the maximum efficiency of 20.7% was obtained at 9.8 keV. Photon flux was estimated to be ∼4×108 photons/s. A system for a scanning x-ray microscope has been constructed and the transmission and/or fluorescence microscopy has also been performed.

It is important to enhance the reflectivity of multilayer supermirrors in 10-100 keV region used for hard x-ray optical systems. For this purpose design methods of multilayer supermirrors have been investigated at the grazing angle of 0.3 degrees by means of the x-ray etalon or phase matching configuration. It means that the 1st and higher order Bragg reflections emanated from different periodic lengths cooperatively enhance the reflectivity at energy bands concerned. The x-ray etalons method is useful for multi-band mirror with the band width of 5 keV or so, but becomes a bit difficult to make the energy band wider connecting gaps between isolated bands. Because heavy oscillation of reflectivity curve occurs due to adjacent destructive and constructive interference. The phase matching method is useful to get smooth reflectivity in the broad energy band and is possible to enhance the 2nd order Bragg reflection in higher energy region. We present the design of hard x-ray telescope sensitive in 25-40 keV region by means of multi-block supermirrors of Pt/C multilayers. The effective area was obtained to be more than 100 cm2.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Applications of electric and/or magnetic filters to Rutherford backscattering (RBS) and elastic recoil detection analysis (ERDA) were studied with the aim of improving their performance such as detection limit and depth resolution. A novel RBS technique combined with a charged particle energy filter (CPEF) has been proposed for the detection of contaminants on Si wafers. The CPEF is an electric deflector of charged particles. In this technique, it is placed between a sample and a detector and plays the role of filtering undesirable backscattered signals originated in silicon atoms in the sample from contaminant signals. Experimental results have shown that the CPEF can suppress the silicon signals selectively and appreciably. Another study has been done for ERDA technique using a charge particle energy filter (CPMF) for the analysis of hydrogen depth profile on the surface of a sample. The CPMF is a magnetic deflector of charged particle. It works to remove high energy backscattered particles. As a result, the thickness of the foil in front of a detector can be thinner. The results of calculation have shown that the thickness can be reduced by around 40%.

A new type of high voltage generator has been designed with the aim of developing a compact, inexpensive and easily maintained generator for energetic ion beam analyses such as Rutherford backscattering and particle induced X-ray emission. It consists of several rotating disks and fixed plates made of insulator with metal plates. Since the structure is similar to a rotating disk-type generator, such as the Disktron, it should basically have the potential to display indicators such as compact size and reliable generated voltage stability. Its generating mechanism is, however, rather similar to rectifier-type generators, such as the Cockcroft- Walton and the Schenkel types, so that there are no friction components which might produce a lot of dust, thus opening the high pressure tank for cleaning is an infrequent operation. The proposed generator can be produced relatively inexpensively. A single module model has been built and its generating ability was studied. As a result, it was confirmed that the proposed generating mechanism functions successfully.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new styled compact wavelength dispersive X-ray spectrometer for light elements analysis has been developed. This spectrometer was applied for soft X-ray detection (energy less than 1 keV) mounted on a compact high-energy ion microprobe system `mikro-i' and combined with particle-induced X-ray emission in this system. Two multilayer monochrometers, W/Si multilayer and Ni/C multilayer, settled on the compact multilayer benders for X-ray diffraction, and a gas proportional counter with a wide (150 mm X 20 mm) and thin (1 micrometers thickness) polymer film window for soft X-ray made it possible to achieve the compact dimensions of the spectrometer. This system was evaluated for K lines emitted from light elements such as boron, carbon, nitrogen and oxygen. The energy resolution less than 21 eV for each element was observed and was enough to discriminate their characteristic X-rays from disturbing ones. Also, the sensitivity was enough to analyze trace elements or microarea.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We have developed a parallel X-ray microbeam of 7×5 µm2in size with a small angular divergence, which aims high-resolution strain measurements in a very local area. The microbeam has been formed by compressing and collimating the X-rays from a third-generation undulator source using successive asymmetric reflections. Using this beam, we have evaluated the strain induced by field oxidation in silicon wafers by rocking curve measurements. We have observed that the lattice constant in the Si region near the oxide film edge is contracted and that in the SiO2/Si region is extended. The difference between these lattice constants is as small as about Δd/d∼±5×10-6.

Results of phase-contrast X-ray imaging are presented. The optical system employed consisted of a successive arrangement of horizontal and vertical (+, -) double crystals taking asymmetric Bragg reflection with an asymmetry factor of ∼0.2. The original beam size was thus expanded in both directions and the field of view actually obtained was ∼5×5 mm2. Boundary structures in samples were clearly observed with much higher contrast than those obtained in conventional absorption-contrast imaging. Since this method works in real time, it will provide a new X-ray imaging diagnosis technique for in situ observation over a large area of the samples.

The diamond crystals with a (100) or a (111) surface are characterized by the uses of rocking curve measurements, reciprocal lattice mapping and Lang topography method. The full widths at the half maxima of the rocking curves at the X-ray energy of 8.04 keV have been measured to be 6.5 arcsec and 6.3 arcsec for 400 and 111 Bragg reflection, respectively. While the value for 400 reflection is 1.3 times larger than the theoretical value, that for 111 reflection is almost the same as the theoretical one. A sub-peak of about 15 arcsec leaning to the main peak is clearly seen in the reciprocal lattice maps of (100) crystals. No sub-peak can be seen in those of (111) crystal. In addition, some streaky intensity distribution due to a dynamical effect of the X-ray diffraction, being elongated in the radial direction from the reflection point, is clearly seen. This means that crystallinity of (111) planes is more perfect. From the (100) Lang's topographs, it has also been clarified that the diamond crystals include some defect bundles inside the crystals.