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The alignment and angular dependences of the coercivity of (Sm, Ce)2(Co, Fe, Cu, Zr)17 magnets were investigated. The coercivity of an aligned magnet is slightly larger than that of the isotropically aligned magnet. This result differs from those of Nd–Fe–B sintered magnets and ferrite magnets. In regard to the angular dependence, the coercivity of (Sm, Ce)2(Co, Fe, Cu, Zr)17 magnets decreases from 0° to 40° and increases thereafter. The trend is similar to that observed in Ga-doped Nd–Fe–B sintered magnets and ferrite magnets and reproduces those expected from a Stoner–Wohlfarth model or a coherent rotation of magnetization, even though the magnetization reversals for these magnets proceed through the motion of magnetic domain walls. The angular dependence of the coercivity of isotropically aligned magnets agrees well with the calculation results for angles up to 50° obtained under the assumption that the magnetization of every grain reverses independently through the motion of magnetic domain walls. These results support strongly the conclusion that the coercivity of Ga-doped Nd–Fe–B sintered magnets and ferrite magnets, both which have an angular dependence similar to (Sm, Ce)2(Co, Fe, Cu, Zr)17 magnets, is determined by the motion of magnetic domain walls.

The alignment dependence and angular dependence of coercivity (ALDC and ANDC, respectively) of aligned and isotropically aligned Ga-doped Nd14.79Ga0.57B5,24Co1.11Febal sintered magnets were analyzed, and the results were compared with those of ferrite magnets, which were reported in our previous paper. The coercivity of Ga-doped Nd-Fe-B magnets decreases as alignment improves. The ALDC of this magnet is similar to that of ferrite magnets. The angle of the magnetization-reversal area (AMRA) of the aligned Ga-doped magnets has at coercivity an angular tilt of 41.4°, which is wider than that of the ferrite magnets. The ANDC of Ga-doped Nd-Fe-B sintered magnets displays similar behavior with that of ferrite magnets but is slightly lower than that of ferrite magnets, which is expected from AMRA of Ga-doped Nd-Fe-B sintered magnets. These results support our proposed coercivity mechanism; specifically, the magnetic domain walls are pinned at grains with tilted easy magnetization directions or $c$ -axis tilted from the easy magnetization of the magnet. When the magnetic domain walls are de-pinned from the pinning sites, they jump through several grains, thereby determining the coercivity.

We investigated the local strain in a silicon carbide (4H-SiC) (0001) trench metal-oxide semiconductor field-effect transistor (MOSFET) using synchrotron nanobeam X-ray diffraction (nano-XRD) at the SPring-8 BL13XU beamline. Using X-rays incident on the 4H-SiC trench cross section, diffraction measurements were performed on the ( 11 2 ¯ 0 ) and ( 11 2 ¯ 4 ) planes. Intensity maps of the 11 2 ¯ 0 and 11 2 ¯ 4 diffractions yielded images reflecting the trench structure. The spatial resolution of the 4H-SiC 11 2 ¯ 4 intensity map in the [0001] direction was higher than that for the 11 2 ¯ 0 diffraction because the angle of incidence was close to perpendicular to the sample. From two-dimensional reciprocal space maps of the symmetric and asymmetric diffractions, the tilt and the ( 11 2 ¯ 0 ) - and (0004)-plane strain components were individually separated and visualized. A tensile strain of approximately 0.1% was found in the region between the trenches. These results indicate the effectiveness of nano-XRD for strain visualization in trench MOSFETs and similar electronic devices.

We report current status of a synchrotron nanobeam X-ray diffraction (nanoXRD) station at SPring-8. The nanoXRD station is located at the 4th experimental hutch of the surface and interface structure beamline BL13XU. The 4th hutch, that was constructed in March 2015, is dedicated for the nanoXRD experiments. There are two types of focusing optics available at the station; a zone plate (ZP) and compound refractive lenses (CRLs). The ZP is used to focus X-rays with energy range from 8 to 15 keV. The minimum beam size of 110 × 150 nm2 is available with the ZP. CRLs made of quartz glass are used for high energy X-rays up to 30 keV. Beam size at 30 keV is 1.6 × 1.6 µm2 and the flux is 1.2 × 1010photons/s. Our main target samples are single crystalline thin films or nano-rods grown on substrates. Cross sectional observations of thick film have also been started. Users can align samples to the rotation center of the goniometer rapidly by preparation using an offline stage that is synchronized to an online stage. In addition, we have developed semi-automatic sample alignment system, that can align any position on a sample surface to the rotation center even if the sample has non-flat surface, like badly cleaved section of a crystal. Details of the station and equipments are introduced.

Au redistribution layers 10 to 100 μm wide were fabricated on heterogeneously integrated advanced flexible hybrid electronics (FHE) substrates formed by a die-first approach based on fan-out wafer-level packaging. The formed Au metal wiring was meticulously studied for locally induced mechanical stress upon bending (bending radius, BR 20 mm) using Laue microdiffraction (LμD) with synchrotron radiation. It was inferred from the LμD data that upon bending the FHE substrate up to the BR of 20 mm, the Au metal wiring (10 mm long, 100 μm wide, and 500 nm thick) experienced mechanical bending stress amounting to 250 ∼ 300 MPa. The stress values obtained from the LμD studies were close to the stress value of 350 MPa obtained by simulation.

We investigated magnetization reversal of (Sm, Ce)2(Co, Fe, Cu, Zr)17 magnets as per x-ray magnetic circular dichroism microscopy. Magnetization reversal initially occurs at the ferromagnetic grain boundaries or in the vicinity of nonmagnetic Sm oxides. As the demagnetization field increases after magnetization reversal, the reversal region extends into the grain from these areas by the magnetic domain wall motion. Energy-dispersive x-ray analysis using an electron probe micro-analyzer shows that, at the grain boundaries, the Fe concentration is higher and the Cu concentration is lower compared to that inside of the grains; and concentrations of Sm, Co, Fe, and Cu vary in the vicinity of Sm oxides. By measuring the Co L3 absorption intensity, we verified that local coercivities in these areas are very low compared to those inside of the grain. These results imply that the magnetization reversal that occurs in these areas is induced by the variation in the composition. The results obtained in our research will be useful for improving the magnetic properties of Sm–Co magnets.

We quantitatively evaluated lattice plane microstructure, which includes lattice plane tilt, spacing, twist, and their fluctuations, in a modified Na-flux GaN bulk single crystal using the synchrotron-based nanobeam X-ray diffraction method. The GaN crystal was fabricated by two-step growth; the first layer had coalescence boundaries as a consequence of faceted growth from the multipoint-seed GaN template, and the second layer grew on the first without faceted growth. Position-dependent ω-2θ- mapping analysis revealed in-plane distribution of local lattice plane microstructure along with dislocation morphology around the coalescence boundary and the growth-stage boundary (GSB). Faceted growth from the multipoint seed template led to concentration of a-type dislocations at the coalescence boundary. These dislocations would glide widely on basal planes above the GSB, and then homogeneously propagate toward the surface. As a result, the modified Na-flux GaN crystal had a homogeneous lattice plane microstructure with little bunching of threading dislocations.

Boron-doped ultrananocrystalline diamond (UNCD)/nonhydrogenated amorphous carbon (a-C) composite (UNCD/a-C) films were prepared by coaxial arc plasma deposition (CAPD) with boron-blended graphite target. Their growth was achieved at room temperature and a base pressure of less than 10-3 Pa (no inflow gas) owing to CAPD, whereas the growth of UNCD films by chemical vapor deposition generally requires high substrate temperatures of more than 700°C and a hydrogen ambient gas. The formation of p-type conduction was confirmed thermally, namely Seebeck effect, and heterojunction diodes formed with n-type Si exhibited a typical rectifying action. It was demonstrated that CAPD is advantageous to the practical film formation including doping.

For fine three-dimensional observations of large biomedical and organic material samples, we developed a high-resolution X-ray CT system. The system consists of a sample positioner, a 5-μm scintillator, microscopy lenses, and a water-cooled sCMOS detector. Parallel beam geometry was adopted to attain a field of view of a few mm square. A fine three-dimensional image of birch branch was obtained using a 9-keV X-ray at BL16XU of SPring-8 in Japan. The spatial resolution estimated from the line profile of a sectional image was about 3 μm.

We report the atmospheric pressure chemical vapor deposition (CVD) growth of single-layer graphene over a crystalline Cu(1 1 1) film heteroepitaxially deposited on c -plane sapphire. Orientation-controlled, epitaxial single-layer graphene is achieved over the Cu(1 1 1) film on sapphire, while a polycrystalline Cu film deposited on a Si wafer gives non-uniform graphene with multi-layer flakes. Moreover, the CVD temperature is found to affect the quality and orientation of graphene grown on the Cu/sapphire substrates. The CVD growth at 1000 °C gives high-quality epitaxial single-layer graphene whose orientation of hexagonal lattice matches with the Cu(1 1 1) lattice which is determined by the sapphire’s crystallographic direction. At lower CVD temperature of 900 °C, low-quality graphene with enhanced Raman D band is obtained, and it showed two different orientations of the hexagonal lattice; one matches with the Cu lattice and another rotated by 30°. Carbon isotope-labeling experiment indicates rapid exchange of the surface-adsorbed and gas-supplied carbon atoms at the higher temperature, resulting in the highly crystallized graphene with energetically most stable orientation consistent with the underlying Cu(1 1 1) lattice.

We developed compound refractive lenses made of quartz glass for wide range of X-ray energy and investigated the focusing performance. The lenses for X-ray energy of 10, 12.4, 15, 20, 25, 30 keV were fabricated by optical lithography and dry etching techniques. Two lenses with the focal distance of 100 and 200 mm were combined in a crossed geometry to achieve two dimensional focusing. The measurements of the focusing properties were performed at beamline BL13XU in SPring-8 with a high-resolution microdiffraction system. The microbeams with the beam size less than 3.2 μm in both vertical and horizontal direction were obtained at all the energies. We also investigated the influence of the local lens condition to the focusing ability. It is found that the focal position moved depending on the illuminated position on the lens due to the shape errors, which causes the increase of the total beam size.

This work quantitatively assessed the three-dimensional distribution of crystal lattice distortions in an epitaxial AlN thick film grown on a trench-patterned template, using nanobeam X-ray diffraction. Position-dependent ω-2θ-φ mapping clearly demonstrated local tilting, spacing and twisting of lattice planes as well as fluctuations in these phenomena on a sub-micrometer scale comparable to the pitch of the trench-and-terrace patterning. Analysis of the crystal lattice distortion in the depth direction was performed using a newly developed method in which the X-ray nanobeam diffracted from the sample surface to specific depths can be selectively detected by employing a Pt wire profiler. This technique generated depth-resolved ω-2θ-φ maps confirming that fluctuations in lattice plane tilting and spacing greatly depend on the dislocation distribution and the history of the AlN epitaxial growth on the trench-patterned structure. It was also found that both fluctuations were reduced on approaching the AlN su...

We have previously reported that -AlN crystallites with diameters of 0.5–1 µm were occasionally grown on sapphire(0001) by pulsed laser deposition, which implied that the migration mobility of the species deposited on the substrate surface might be an insufficient for the film growth of -AlN. In the present study, in order to enhance the crystal growth of -AlN, sapphire(0001) substrates with an atomically smoothness (step-sapphire) were employed. The growth conditions of - and -AlN extended to higher nitrogen-pressures, as compared to those using normal surface sapphire(0001) substrates (normal-sapphire). This is due to the enhancement in the mobility of the deposited species on the substrate surface.

Growth of ultrananocrystalline diamond (UNCD)/hydrogenated amorphous carbon (a-C:H) composite films without initial nucleation was realized by an coaxial arc plasma gun at a substrate-temperature of 550 °C and hydrogen-atmosphere of 53.3 Pa. The pulsed arc discharge was triggered at a repetition rate of 1 Hz. The deposition rate was 80 nm/min. X-ray diffraction measurements with 12-keV X-rays from synchrotron radiation indicated extremely broad rings from diamond and none from graphite. The UNCD crystallite diameters were estimated to be approximately 1.3 nanometers by using Scherrer’s equation. The sp3/(sp2+sp3) was estimated to be approximately 57% from the X-ray photoemission spectroscopy. The coaxial arc plasma gun is a new powerful method that might enable us to realize the supersaturated condition with highly energetic ions for the growth of UNCD.

Surface structure of Pt(3 1 0) = 3(1 0 0)–(1 1 0), which contains kink atoms in the step, has been determined with the use of in situ surface X-ray scattering (SXS) in the double layer region (0.50 V(RHE)) in 0.1 M HClO 4 . Clean Pt(3 1 0) surface has pseudo (1 × 1) structure on which lateral displacements of 2–9% and 0.3–1% are found along a and b directions, respectively, whereas the surfaces of Pt(1 1 0) = 2(1 1 1)–(1 1 1) and Pt(3 1 1) = 2(1 0 0)–(1 1 1) are reconstructed to (1 × 2) according to previous reports. Interlayer spacing between the first and the second layers d 12 is contracted about 5% compared with the bulk spacing, whereas those between underlying layers are expanded down to fourth layer. Fully adsorbed CO has no effect on the surface structure of Pt(3 1 0). This result differs from that on Pt(1 1 1), where d 12 is expanded after CO adsorption.

Using synchrotron X-ray diffraction we have determined the atomic arrangement of a two-dimensional lattice of thallium (Tl) nanodots self-assembled on the Si(1 1 1)-7 × 7 surface at room temperature. By analyzing a set of in-plane reflections as well as crystal truncation rods, we find that the atomic structure of a single Tl nanodot is best described by a dynamical model where nine Tl atoms are arranged 0.91 ± 0.19 A above the substrate Si adatoms with three central atoms slightly bulging over the surrounding six atoms by about 0.18 A. Our model further suggests that the Tl atoms are quite mobile within the attractive basins of the frozen substrate 7 × 7 surface. The mobile nature of Tl atoms naturally explains the blurred scanning tunnelling microscope images and may also provide a clue to understand the intriguing metallic feature of the Tl nanodots.

The surface structure of Si(1 1 1)–6 × 1-Ag was investigated using surface X-ray diffraction techniques. By analyzing the CTR scattering intensities along 00 rod, the positions of the Ag and reconstructed Si atoms perpendicular to the surface were determined. The results agreed well with the HCC model proposed for a 3 × 1 structure induced by alkali-metals on a Si(1 1 1) substrate. The heights of the surface Ag and Si atoms did not move when the surface structure changed from Si(1 1 1)–√3 × √3-Ag to Si(1 1 1)–6 × 1-Ag by the desorption of the Ag atoms. From the GIXD measurement, the in-plane arrangement of the surface Ag atoms was determined. The results indicate that the Ag atoms move large distances at the phase transition between the 6 × 1 and 3 × 1 structures.

We have determined the structure of the 4H–SiC(0 0 0 1)-3 × 3 surface after exposure to small amounts of molecular oxygen at room temperature using surface X-ray diffraction. The 3 × 3 reconstruction remains until at least an exposure of 10,000 L, but the diffracted intensities change, indicating structural changes. Comparison of the Patterson maps of the clean and oxidized surface shows that the main changes occur at the Si tetramer on top of the 3 × 3 surface. Atomic positions for several models were fitted to the experimental data. A model in which oxygen atoms are inserted into the Si tetramer gives the best fit to the experimental data. The best-fit atomic positions agree well with those obtained using density functional calculations.

The topmost and inner layer structures of Ru(0001)-(2 × 2)-O have been determined by surface X-ray diffraction. The periodical peaks near integer positions were observed along the fractional order rod. Adsorbed oxygen causes relaxation and rumpling in the deeper layer as well as in the topmost layer. Atomic displacement from the bulk position decreases exponentially with depth below the second layer. The topmost Ru−Ru interlayer spacing and Ru−O bond length are consistent with those obtained from DFT calculations and dynamical LEED measurements reported previously.

We have performed high sensitive imaging of the atomic arrangement of Ge buried in a Si crystal as Ge clusters using the internal detector scheme of X-ray fluorescence holography. The atomic arrangement of Ge buried in a Si crystal is expected to have the strained diamond structure. We have measured holograms of a thin Si/Ge multilayer film composed of thin Si layers and Stranski–Krastanov Ge islands using a crystal analyzer in combination with synchrotron radiation. The atomic arrangement reconstructed from the holograms shows that the Ge islands are indeed of the diamond structure. Comparison of atomic arrangements reconstructed from experimental and simulated holograms allows us to determine the average lattice constant of the Ge islands. The lattice constant obtained shows that the Ge islands are partially relaxed in Si matrix lattice.

The surface structure of the 3 × 3 reconstruction of the 4H-SiC (0 0 0 1) surface was investigated with surface X-ray diffraction (SXRD). Of the studied models, the twist model proposed by Starke et al. [U. Starke, J. Schardt, J. Bernhardt, M. Franke, K. Reuter, H. Wedler, K. Heinz, J. Furthmuller, P. Kackell, F. Bechstedt, Phys. Rev. Lett. 80 (1998) 758] gave the best fit to the experimental data. The structural parameters were determined accurately.

The structure of the Si(1 1 1)-6 × 1-Ag surface is investigated using crystal truncation rod (CTR) scattering along 00 rod. For the measurement, we developed a manipulator suitable for observing CTR scattering at large momentum transfer perpendicular to the surface. The heights of the silver and reconstructed silicon atoms from the substrate were determined. We also compared the obtained positions with those of the Si(1 1 1)-√3 × √3-Ag surface and found that the heights of those reconstructed atoms are almost the same.

We have studied the crystallization process of HfO 2 and HfAlO x films using grazing incidence X-ray diffraction (GIXRD) with synchrotron radiation. The HfO 2 and HfAlO x films were grown by atomic layer deposition (ALD) on a chemical SiO 2 interfacial layer. X-ray diffraction (XRD) patterns of the HfO 2 film as-deposited contain not only the monoclinic phase but also the orthorhombic or tetragonal phase. With increasing annealing temperature, the orthorhombic or tetragonal phase decreases and disappears. The HfAlO x film crystallized after annealing at 900 °C. The crystallographic phase was the cubic phase of CaF 2 type.

We describe a sample holder assembly which can control a sample temperature in a wide range. The assembly is attached to a six-circle surface X-ray diffractometer with an ultrahigh-vacuum chamber. Samples up to 16.5 mm square can be held at constant temperatures between 50 and 1350 K with a tantalum heater on a pyrolytic boron nitride plate and a closed-cycle helium refrigerator. The accuracy of a sample temperature is 3 × 3 -Ag surface.

Surface-structure analysis of a disordered 2 × 2 phase on Pt(1 1 1) was carried out utilizing surface X-ray diffraction under grazing incidence condition with a synchrotron X-ray beam (SPring8, Nishiharima). The structure of an ordered Pt(1 1 1)-p(2 × 2)–O surface started losing its threefold symmetry immediately after 3 min of X-ray beam irradiation at 25 K. A disordered new phase of a Pt(1 1 1)-2 × 2 surface was stabilized and supplied to intensity measurements. Structure analysis using Texan software of the new phase of the Pt(1 1 1)-2 × 2 surface revealed the existence of remarkable displacements of platinum atoms over ten surface platinum layers in contrast to the buckled Pt(1 1 1)-2 × 2–O surface structure observed by LEED. The maximum in-plane and out-of-plane displacements from the bulk-phase positions were found to be 0.017(5) and 0.040(5) nm, respectively.

A new technique to observe mesoscopic-range strain fields (up to several hundreds of nm) is proposed, using modulation of the crystal-truncation-rod (CTR) scattering caused by Bragg reflection. This technique is particularly sensitive to small, long-range strain fields near crystal surfaces and interfaces, which are usually difficult to be discriminated by using Bragg reflection. A simple interpretation can be made for the modulation profile: the technique is physically simple with a few parameters fitted to the data and, independently of any model, is able to determine the total displacement due to mesoscopic strain field for depths up to several hundreds of nanometers. We applied this method to a Si(0 0 1) wafer whose surface is covered with a thermal oxide layer 3 nm thick. On the basis of the expressions we obtained for the modulation profile a least-squares fitting was carried out to give a result that under the oxide layer there exists a total displacement of −0.16 A. It was also revealed from the visibility of the modulation profile that the total displacement has a static fluctuation of at least ±0.13 A in the lateral direction. The new method can be used for the correction of the errors of the X-ray standing wave (XSW) method produced by strained layers near crystal surfaces.

A phase retrieval method for noncrystalline surface layers that involves intensity modulation of the specular reflection under the excitation of a Bragg reflection was applied to a Si(001) single crystal covered with a native oxide layer of a few nanometers thickness. The phases and moduli of the amplitudes of the scatterings from the native oxide layer were uniquely retrieved at three points on the specular truncation rod. The phases and moduli obtained experimentally were consistently explained by a model of a Si(001) single crystal covered with a uniform oxide layer with a rough surface.

The structure of the [Formula: see text] surface was studied at both room temperature and a low temperature of 50 K using grazing incidence X-ray diffraction. At low temperatures diffuse scattering was observed in addition to Bragg reflection. Least squares analyses for Bragg reflections using anisotropic Debye–Waller factors show that the structure at 50 K is consistent with an inequivalent triangle (IET) model, while the structure at room temperature is explained by a honeycomb-chained triangle (HCT) model with strong anisotropic Debye–Waller factors. From the temperature dependence of diffuse scattering, the phase transition temperature Tc and critical exponent β were determined to be about 150 K and 0.27. Some Bragg intensities showed discontinuous changes in their first derivatives at Tc. The results favor a displacive phase transition rather than an order–disorder one.

The dislocation morphology and lattice distortion, including the tilting and twisting of lattice planes, at the Na-flux GaN/seed-GaN interface were investigated using transmission electron microscopy (TEM) and position-dependent nanobeam X-ray diffraction (nanoXRD). The results revealed that the dislocation morphology and lattice distortion in Na-flux GaN at the initial growth stage are strongly influenced by the seed-GaN surface morphology and the growth mode of Na-flux GaN. From the TEM results, one can observe that the formation of dislocation-related etch pits (DREPs) on the seed-GaN surface and the three-dimensional (3D) growth mode for Na-flux GaN give rise to the bending and lateral propagation of dislocations penetrating from the seed-GaN to the Na-flux GaN. This simultaneously results in homogenization of the GaN crystal domain structure as confirmed by nanoXRD. The mechanism responsible for the bending and lateral propagation of dislocations by the formation of DREPs and the 3D growth mode for t...

The in-plane structure of Si(1 1 1) 21 × 21 -(Ag+Au) surface was studied by using grazing incidence X-ray diffraction method. A total of 72 inequivalent fractional order reflections were obtained. The structural models are investigated including the previously proposed models. It is found that the Ag triangles and Si trimers are induced to displace considerably from the honeycomb chained triangle arrangement by the adsorption of Au atoms. From the analysis, the models with five Au atoms in the unit cell, which have the Au–Au interatomic distance peculiar to the 21 × 21 periodicity, are favored.

It is found by simulations that three-dimensional images of surface atoms can be reconstructed from the intensity data along rods in surface X-ray diffraction. The intensity variations along the rods are interpreted as a hologram created by the interference between the diffracted wave by the known substrate and that by the unknown surface structure.

We investigated influences of a repetition frequency of laser pulses on growth of AlN crystalline films by pulsed laser deposition. The structural and morphological properties of the films were studied by X-ray diffraction and scanning electron microscopy. Employment of high frequency laser pulses not only enhanced the growth of AlN crystallites, but also afforded the crystal growth at higher nitrogen pressures. Growth of α-AlN was dramatically enhanced with an increase in the laser pulse frequency, while β-AlN was grown at the high frequency of laser pulses and high nitrogen pressures.

Nitrogenated ultrananocrystalline diamond/hydrogenated amorphous carbon composite films were prepared in a hydrogen and nitrogen mixed-gas atmosphere by pulsed laser deposition with graphite targets. The electrical conductivity in n-type conduction remarkably increases to 18 §Ù–1×cm–1 at 300 K with an increase in the nitrogen content up to 7.9 at.%. In the nitrogen content range from 7.9 to 10.4 at.%, the electrical conductivity is suddenly and dramatically decreased down to 0.03 §Ù–1·cm–1 in reverse, accompanied by the disappearance of diamond grains in the films. A huge number of grain boundaries owing to the existence of diamond grains embedded in UNCD/a-C:H films, which is structural specific to UNCD/a-C:H, should play a significant role in the large electrical conductivity enhancement by nitrogen doping. The X-ray photoemission and near-edge X-ray fine-absorption spectroscopic measurements could not detect an evident difference in the spectra that explain the sudden irregular change in the electrical conductivity.

The interface structure of an amorphous-Si/1ML-Ge/Si(001) crystal was investigated by the X-ray standing wave (XSW) method. The sample was prepared by the molocular beam epitaxy (MBE) deposition of 1ML of Ge on a clean Si(001) surface followed by the deposition of an amorphous Si (a-Si) capping layer of 50 A thickness. The intensity of the reflected X-rays and the yield of the fluorescent X-rays of GeKα were measured around the 111 Bragg point. The fluorescence yield curve, which indicates the interaction between the XSW field and Ge atoms, showed that most of the Ge atoms stay at a position very close to the ideal Si site. This result provides effective feedback for fabricating SixGe1-x/Si devices.

We have developed a method of determining directly the structure of surfaces and interfaces as three-dimensional images using X-ray diffraction. The intensity profile along an integral order rod is interpreted as an interference pattern between scattered waves from a substrate whose structure is already known and from surface layers whose structure is the target of investigation. This mechanism is the same as that of holography and has a potentiality to reconstruct electron density. Atomic images of Ge in a-Si/Ge/Si(001) have been obtained by this method.

Polycrystalline thin films of La-substituted bismuth titanate (BLT) were formed directly on p-type Si(100) substrates by using sol-gel and spin coat methods. The BLT film and interfacial layer between BLT and Si were quantitatively investigated by the X-ray reflectivity method. Also, crystal orientations of sub-100-nm-thick BLT thin films were confirmed by X-ray diffraction using a synchrotron radiation source. The preferred c-axis orientation normal to the surface depended on the crystallization temperature. The difference in the preferred c-axis orientations of the BLT films caused the difference in the hysteresis voltage width in the capacitance-voltage characteristics of Au/BLT/p-Si structures. Furthermore, the c-axis of the Bilayered structure was preferentially oriented and aligned in the in-plane direction.

Surface structure of a stepped surface of Pt, Pt(311) (=2(100) − (111)), has been determined under potential control in 0.1 M HClO4 with the use of in situ surface X-ray scattering (SXS). The crystal truncation rods (CTRs) are reproduced well with the (1 × 2) missing-row model. Relaxation of surface layers, which is observed on the low-index planes of Pt, is not found on Pt(311) in the “adsorbed hydrogen region”. CTRs at 0.10 (RHE) have the same feature as those at 0.50 V, showing that the surface layers of Pt(311) have no potential dependence. Scanning tunneling microscopy (STM) also supports the (1 × 2) structure of Pt(311) in 0.1 M HClO4.