bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monitoring of Out-of-Plane Displacement of Hot Medium and Mechanism of Fused Silver Solder Cracking Estimated by Quantitative Acoustic Emission Source Wave Analysis
Authors: Kentaro Hayashi Kentaro Hayashi , Hiroaki Suzuki Hiroaki Suzuki , Mikio Takemoto Mikio Takemoto 
Published: October 2002

This study aims to elucidate the fracture kinetics of microcracks formed during fused metal degradation of austenitic stainless steel by the acoustic emission (AE) source inversion processing. To accomplish this purpose, we developed a new heat-resistant capacitive AE sensor to measure the out-plane displacement excited by elastic waves. Wave attenuation and velocity dispersion in hot stainless steel were measured by a laser ultrasonic technique. A new source inversion processing algorithm, accounting for both the velocity dispersion and wave attenuation, was proposed. We observed a number of AE signals from Mode-I cracks during fused silver solder degradation of stressed AISI304 steel at 1000 K. The size of microcracks estimated by the source inversion processing was found to be equivalent to the size of one or two crystal grains. Crack propagation velocity reached 40 m/s and was almost 109 times that estimated by an optical microscope. It is revealed for the first time that cleavage cracks are formed rapidly during fused metal degradation.
Improvement of Magnetostatic Coupling in Reversal Magnetically Induced Superresolution
Authors: Kawano Toshifumi , Hidetaka Ito Hidetaka Ito , Hidemi Yoshida Hidemi Yoshida 
Published: October 2002

Reversal magnetically induced super resolution (R-MSR) makes use of magnetostatic coupling, which is a very weak force, in contrast to exchange coupling. To avoid the disturbance by the unexpected external field during readout (H

r
), methods for improving the magneto static coupling were studied. The direction of magnetization in the grooves markedly affected the H

r
dependence. When the grooves were erased in the direction antiparallel to that of lands, the H

r
stability showed symmetrical dependence on the direction of applied field. Moreover, adding a flux sink layer on the memory layer was effective for improving H

r
stability on long recording marks. This layer induced leakage flux from the center of the long recording mark. Consequently, the readout field stability of 170 Oe could be obtained with a 1.6 µm mark length.
Zero-Loss Reflection High-Energy Electron Diffraction Patterns and Rocking Curves of the Si(111)7×7 Surface Obtained by Energy Filtering
Authors: Yoshimi Horio Yoshimi Horio 
Published: October 2002

The improvement of a new type of reflection high-energy electron diffraction (RHEED) apparatus equipped with a retarding field analyzer is reported. Three kinds of meshes are examined for the retarding grids of the analyzer and their energy resolutions are checked. Electron beam trajectories passing through the analyzer are also simulated and the calculated spot sizes and shapes are compared with experimental ones. Very fine 250 mesh, used for the retarding grid, gives very good energy resolution of ΔE=4 eV with an incident beam energy of E=10 keV, and therefore ΔE/E = 4×10-4. Energy-filtered RHEED patterns and energy-filtered rocking curves are taken for the Si(111)7×7 surface and are compared with conventional ones. The advantages and characteristics of energy filtering are described in detail. Improved energy loss spectra for the 0 0 and 1 1 reflected beams are also presented. These clearly show surface plasmon loss peaks.
Electrooptic Measurement of Three-Dimensional Nonuniform Electric Field Mapping in Nitrobenzene
Authors: Ihori Haruo , Uto Sadahito , Kiyomitsu Arii Kiyomitsu Arii 
Published: October 2002

An electrooptic method is useful for measuring electric fields without disturbing them. Our investigations have been concerned with measurements of electric field distribution. Three-dimensional nonuniform electric field distributions were measured in nitrobenzene using the Kerr electrooptic measurement. The field distributions to be measured were produced in a sphere-to-sphere electrode system. The optical system consisted of a He–Ne laser, a polarizer, a quarter-wave plate, an experimental cell, an analyzer, and a photodetector. When a negative high voltage pulse was applied to the electrode system, the light intensity transmitted to the analyzer was measured using the photodetector. Intensity measurements were carried out at many points from θ= 0 to π around the electrode system. From the data obtained, the electric field distribution, i.e., the strength and direction of each electric field vector in the measured plane, was reconstructed using a computed tomography (CT) technique. The measured distributions were compared with the theoretical ones calculated using an analytical method.
State-Space Intercept Method for Seek Control of Optical Disk Drives
Authors: A. Fennema Tetsuo Semba 
Published: October 2002

This paper proposes a novel digital seek control method which guarantees a disk drive head moves to the desired trajectory at the next sample. Comparison of the performance with that of a conventional optimal control method by computer simulation showed that this method is more robust to disturbances and unmodeled dynamics, and that the seek time is shorter. This digital control method was implemented on a 5.25-inch MO disk drive of a half-high form factor by using a conventional microprocessor, and it was confirmed that the tracking performance is good and that the average seek time is less than 29 ms.
Formation of SiGe Source/Drain Using Ge Implantation for Floating-Body Effect Resistant SOI MOSFETs
Authors: Akira Nishiyama Akira Nishiyama , Osamu Arisumi Osamu Arisumi , Mamoru Terauchi Mamoru Terauchi , Shiroh Takeno Shiroh Takeno , Ken Suzuki Ken Suzuki , Chie Takakuwa Chie Takakuwa , Makoto Yoshimi Makoto Yoshimi 
Published: October 2002

SiGe was formed by Ge implantation into silicon on insulator (SOI) substrates with the dosage range from 0.5 to 3×1016 cm-2 and subsequent annealing in N2. The implantation dosage dependence of the crystalline quality, bandgap and sheet resistance of the SiGe layers are investigated. The implantation damage for Ge dosage up to 1×1016 cm-2 can be removed at a temperature as low as 700°C. A SiGe crystalline network is formed by the annealing at the same time. With a Ge dosage of 1×1016 cm-2 or more, bandgap narrowing of the SiGe layer was detected. Sheet resistances of SiGe N+ and P+ layers gradually increase for higher Ge dosage. SOI MOSFET characteristics in terms of the floating-body effect with the SiGe source/drain layers are presented. The bandgap narrowing suppresses the floating-body effect of fully depleted SOI MOSFETs, while maintaining the reverse leakage current of the p-n junction between the source/drain and channel at a low level.
Property Change of Si(111) Surface by Scanning Tunneling Microscope Manipulation
Authors: Seiji Heike Seiji Heike , Tomihiro Hashizume Tomihiro Hashizume , Satoshi Watanabe Satoshi Watanabe , Mark I. Lutwyche Mark I. Lutwyche , Yasuo Wada Yasuo Wada 
Published: October 2002

Scanning tunneling microscopy (STM) has been used to form trench lines 0.2–0.6-nm deep and 10-nm wide by applying a high voltage and/or a large tunneling current between the tip and the Si(111)-7×7 surface. We have found that the apparent height of the surface area surrounded by a complete square trench is 0.1–0.3 nm lower than the outside, while no apparent height difference is measured in the case of a square trench with one open corner. We have also observed that the trench formation is hindered or made difficult inside the complete surface square trench, while the effect is negligible in the case of the open trench.
Visible Light Emission from SiOx Films Synthesized by Laser Ablation
Authors: Tetsuya Makimura Tetsuya Makimura , Yasuhiko Kunii Yasuhiko Kunii , Naoto Ono Naoto Ono , Kouichi Murakami Kouichi Murakami 
Published: October 2002

We have developed a method for synthesizing SiOx films with visible light emission, applying a laser ablation technique. The films were formed by depositing laser-ablated silicon particles in oxygen gas diluted with helium gas. Soft X-ray absorption spectroscopy revealed that the composition of the film is controlled by the total pressure of the gas. Films with particular composition exhibit intense red photoluminescence with a peak below 1.5 eV after annealing in argon gas at 1000°C. In addition to this, most of the films exhibit 2.2-eV photoluminescence after annealing at 500°C. On the basis of these results, the origin of the photoluminescence is discussed.
Nanometer-Scale Wires of Monolayer Height Alkanethiols on AlGaAs/GaAs Heterostructures by Selective Chemisorption
Authors: Akio Nagahara Hirotaka Ohno , Shangjr Gwo Shangjr Gwo , Wataru Mizutani Wataru Mizutani , Hiroshi Tokumoto Hiroshi Tokumoto 
Published: October 2002

Self-assembled nanometer-scale wires (SANWs) composed of octadecylthiol [ODT, CH3(CH2)17SH] have been selectively formed on the GaAs surface of an AlGaAs/GaAs heterostructure. The sample grown by metal organic chemical vapor deposition (MOCVD) was cleaved to expose the AlGaAs/GaAs heterostructure in a solution containing the ODT molecules. Both surface properties and morphology of these wires have been investigated simultaneously by scanning probe microscopy. SANWs as narrow as 10 nm in width and ∼1.0 nm in height were observed. The inability to form an ODT monolayer on the AlGaAs surface was attributed to the formation of an oxide layer.
Light Scattering by Submicron Particles on Film–Coated Wafers
Authors: Hideyuki Kondo Hideyuki Kondo , Shigenari Yanagi Shigenari Yanagi , Kazushige Takaishi Kazushige Takaishi , Takayuki Shingyouji Takayuki Shingyouji , Tatsuo Yoshinobu Tatsuo Yoshinobu , Hiroshi Iwasaki Hiroshi Iwasaki 
Published: October 2002

The intensity of light scattered by particles on film–coated wafers was measured as a function of film thickness using two types of particle counter with different optical configurations. The scattered light intensity was found to oscillate periodically with film thickness; the period of oscillation was in agreement with that of the reflectivity of the incident beam, and significant enhancement of scattering intensity was observed for thicknesses less than about 0.3 µm.
Giant Electric Field Effect on Al/BaTiO 3/(Y 0.6Pr 0.4)Ba 2Cu 3Oy Structures
Authors: address:hontsu@info.waka.kindai.ac.jp Shigeki Hontsu \footnoteE-mail , Hitoshi Tabata Hitoshi Tabata , Masaya Nakamori Masaya Nakamori , Junya Ishii Junya Ishii , Tomoji Kawai Tomoji Kawai 
Published: October 2002

Planar metal-ferroelectric-superconductor field effect transistors (MFS-FETs) have been fabricated on SrTiO3 (100) substrates. The FET has the structure of Al/BaTiO3 (BTO) /(Y0.6Pr0.4)Ba2Cu3Oy (YPBCO), where the oxide layers are grown heteroepitaxially by ArF excimer laser deposition using an in situ metal mask changing system. The relative dielectric constant (ε
r) of BTO is 200 at 77 K, and the ferroelectric field effects at low temperature have been measured. The source-drain current (I
SD) is enhanced 28% by applying negative gate voltage of -1.5 V. These results indicate that the Al/BTO/YPBCO structures are favorable for use in the superconducting FET.
Influences of Trabecular Structure on Ultrasonic Wave Propagation in Bovine Cancellous Bone
Authors: Hosokawa Atsushi , Otani Takahiko , Suzaki Takuji , Kubo Yoshiomi , Takai Shinro 
Published: October 2002

Ultrasonic wave propagation in water-saturated bovine cancellous (spongy) bone has been experimentally studied in vitro by a pulse transmission technique. The propagation of fast and slow longitudinal waves in bovine cancellous bone [rf:1] is examined in relation to porosity using Biot's and Wyllie's equations to estimate the measured speeds versus porosity. In the high porosity range, the trabecular structure influences the propagation of the fast and slow waves in cancellous bone.
Ion Assisted Deposition of Crystalline TiNi Thin Films by Electron Cyclotron Resonance Plasma Enhanced Sputtering
Authors: Martin Mišina Martin Mišina , Yuichi Setsuhara Yuichi Setsuhara , Shoji Miyake Shoji Miyake 
Published: October 2002

Electron-cyclotron-resonance plasma enhanced sputtering with magnetic-mirror plasma confinement is characterized by low working pressures and large ion flux densities. TiNi thin films were deposited by this technique onto preheated Si (111) substrates. The crystal structure and composition of the films were analyzed by X-ray diffraction and Rutherford backscattering spectrometry, respectively. The substrate temperature T
cr necessary for deposition of crystalline TiNi films was determined as a function of the ion-to-metal flux ratio j
ion/j
Ti+Ni and ion energy E
i. T
cr as low as 555 K was found for j
ion/j
Ti+Ni=3.9 and E
i=150 eV. Substrate temperatures higher than T
cr resulted in a textured crystal structure. Factors affecting the composition of the deposited thin films are also discussed.
Nanorheology of Polymer Blends Investigated by Atomic Force Microscopy
Authors: Ken Nakajima Ken Nakajima , Hideki Yamaguchi Hideki Yamaguchi , Jeong-Chang Lee Jeong-Chang Lee , Masami Kageshima Masami Kageshima , Takayuki Ikehara Takayuki Ikehara , Toshio Nishi Toshio Nishi 
Published: October 2002

We measured force–distance curves of polystyrene (PS)/poly (vinyl methyl ether) (PVME) blend thin films using atomic force microscopy (AFM) in order to pursue the possible usage of AFM as a tool for detecting viscoelastic properties of polymeric materials from a nanoscopic point of view. In quasi-static measurements of force–distance curves for a sample whose PS content equals 100%, both adhesive force and capillary force were measured separately. A phenomenon possibly assigned to pulling off of polymer chains by an AFM tip could also be observed for a sample whose PS content equals 60%. By changing the velocity of the AFM tip acting on a blend sample whose PS content equals 40%, we confirmed that the law of time–temperature reducibility holds even on such a nanoscopic scale. This blend sample behaved as a viscous fluid at room temperature, while its behavior became glassy when faster movements of the AFM tip were applied. A discussion on the future development of a new field of research which should be called “nanorheology" was also presented.
Ab Initio Molecular Orbital Study of Suppression of Water Absorption and Hydrolysis (F-Removal) of Chemical-Vapor-Deposited SiOF Films by Nitrogen Doping
Authors: Nakasaki Yasushi , Miyajima Hideshi , Hayasaka Ryota Katsumata 
Published: October 2002

We investigated the mechanism of the nitrogen-doping effect on the suppression of water absorption and hydrolysis (F-removal) of fluorine-doped SiO2 (SiOF) films, using the ab initio molecular orbital method with model clusters of three-membered-rings of Si–O bonds with and without N atoms in the siloxane rings ( Si3O3-
n

(NH)

n

F(OH)5 ( n=0, 1)). We focused on the changes in the reactivity of these clusters with OH- in the presence of N in the rings. The calculations revealed the following. Three-membered SiOF rings of Si–O bonds are more stabilized by the OH- coordination and more easily form metastable pentacoordinated-Si intermediates than the unconstrained small SiOF clusters we examined elsewhere. The N-incorporated SiOF ring becomes less reactive with OH- due to the increase in the reaction barrier for HF formation. The incorporated N atoms suppressed the back-bond deformations by forming Si–N–Si linkages.
Contact Angle and Atomic Force Microscopy Study of Reactions of n-Alkyltrichlorosilanes with Muscovite Micas Exposed to Water Vapor Plasmas with Various Power Densities
Authors: Tohru Nakagawa Tohru Nakagawa , Mamoru Soga Mamoru Soga 
Published: October 2002

Monolayers of n-alkyltrichlorosilanes (CH3(CH2)

n
-1SiCl3: Cn) were formed on the surface of Muscovite micas after various numbers of reactive sites were formed on the mica surfaces by exposing the micas to water vapor plasmas whose power, P, varied from 0 to 100 W. Contact angle measurements of the monolayers showed that the coverages of Cn molecules at n≦8 on the mica surfaces increased with an increase in the plasma power on the micas. On the other hand, the coverages of Cn molecules at n>8 on the micas were not so sensitive to the plasma power as those at n≦8. The atomic force microscopy (AFM) observations of the growth process of the monolayers from C18 showed that island structures were formed on the mica surfaces at the low coverages of the monolayers and that each island grew and eventually came into contact with the other islands as the coverage increased. In contrast, island structures were not observed on the mica surfaces during the growth process of C4 monolayers. These results propose a reaction model of Cn molecules with micas, where Cn molecules at n>8 are hydrolyzed with adsorbed water on the micas in the Cn solutions, followed by condensing to form two-dimensional polymerized network domains; Cn molecules at n≦8 are hydrated with the adsorbed water on the micas in the Cn solutions, but the domain sizes of the two-dimensional polymerized network are not so large as those at n>8 because of a limitation of the condensation among the molecules.
Nature of Tip-Sample Interaction in Dynamic Mode Atomic Force Microscopy
Authors: Kageshima Masami , Imayoshi Takahiro , Yamada Hirofumi , Nakayama Kan , Sakama Hiroshi , Akira Kawazu Akira Kawazu 
Published: October 2002

The dependence curve of the resonance frequency shift of a dynamic mode atomic force microscope (AFM) cantilever on the distance between the tip and the sample is examined. For a system with clean semiconductor sample and a metal-coated tip, the obtained curve exhibited a larger frequency shift compared to one with a uncoated Si tip, and an increasing deviation from van der Waals characteristics as the separation decreased. This is due to an additional attractive force which becomes dominant at a small separation. This force is considered to play a crucial role in high-resolution imaging of semiconductor surfaces with a dynamic mode AFM.
Room-Temperature Epitaxial Growth of Ni-Zn Ferrite Thin Films by Pulsed Laser Deposition in High Vacuum
Authors: Takakazu Kiyomura Takakazu Kiyomura , Manabu Gomi Manabu Gomi 
Published: October 2002

Thin films of Ni-Zn ferrite have been epitaxially grown in situ on basal plane sapphires at room temperature by pulsed laser deposition in high vacuum. The films deposited at oxygen pressures of 1×10-5 to 1×10-6 Torr grew with spinel-type crystal structure and (111) planar orientation. X-ray phi scan analysis showed that the [110] direction in the (Ni, Zn)Fe2O4 (111) plane is parallel to the [1100] direction in the sapphire (0001) plane. The films exhibited streaky reflection high-energy electron diffraction patterns, indicating excellent surface smoothness.
Raman Spectra of Ordered Vacancy Compounds in the Cu-In-Se System
Authors: Shigetaka Nomura Shigetaka Nomura , Shin-ichi Ouchi Shin-ichi Ouchi , Saburo Endo Saburo Endo 
Published: October 2002

Raman spectra of ordered vacancy compounds (OVC) of CuIn2Se3.5and CuIn3Se5have been measured at room temperature. Similar nonpolarized Raman spectra are obtained for CuIn2Se3.5and CuIn3Se5. However, polarized Raman spectra are not available for CuIn3Se5because of its unfavorable crystallinity. A signal at 154 cm-1is assigned to be Γ1mode ofD2dsymmetry, originating from the vibration of selenium atoms in thex-y(a-axes) plane. This signal corresponds to the signal at 178 cm-1for CuInSe2of chalcopyrite-type in the Cu-In-Se system. The lowering of Γ1mode frequency for the defect structure is attributed to looser-bound selenium atoms on account of vacancies in the cation sites. Signals assigned as Γ3mode are unexpectedly observed in the geometries allowing the longitudinal optical (LO) modes of Γ4and Γ5symmetries. The respective mode peaks are found to be more dispersive in frequency for CuIn2Se3.5than for CuInSe2.
Rapid Preparation of YBa 2Cu 3O7-x with T c ∼ 90 K Using a Domestic Microwave Oven
Authors: Masatsune Kato Masatsune Kato , Kenji Sakakibara Kenji Sakakibara , Yoji Koike Yoji Koike 
Published: October 2002

High-T
c superconducting samples of YBa2Cu3O7-x
with T
c ∼90 K have been prepared in a short time of 25 min, using a domestic microwave oven operated at 2.45 GHz and 200 W, without any post-heat treatment. Post-heat treatment is not necessary due to improvement of the sample environment during the microwave process. That is, a pellet of mixed powders of raw materials is surrounded by mixed powders of raw materials and subsequently wrapped in glass wool, in order to suppress rapid dissipation of heat from the surface of the pellet. This leads to successful preparation of homogeneous and oxygenated samples of YBa2Cu3O7-x
.
A Cleaning Model for Removal of Particles due to Laser-Induced Thermal Expansion of Substrate Surface
Authors: Lu Yong-Feng , Song Wen-Dong , Ye Kai-Dong , Lee Yuan-Ping , Daniel S. H. Chan Daniel S. H. Chan , Teck-Seng Low Teck-Seng Low 
Published: October 2002

Taking Van der Waals force and cleaning force due to fast thermal expansion of substrate surface induced by pulsed laser irradiation into account, a cleaning model was established for removal of tiny particles from substrate surfaces. The cleaning condition and cleaning threshold can be obtained from this model. Theoretical predictions have been verified by the experimental results for removing quartz particles from silicon substrate. For laser-induced removal of quartz particles from silicon substrate surfaces, the cleaning threshold is about 135 mJ/cm2. Cleaning efficiency increases with increasing laser fluence, and large particles can be removed more easily than small ones.
Rotator Phase Transition through an Intermediate State in Odd n-Alkanes: In Situ Optical Observation Study
Authors: Koji Nozaki Koji Nozaki , Takashi Yamamoto Takashi Yamamoto , Tetsuhiko Hara Tetsuhiko Hara , Masamichi Hikosaka Masamichi Hikosaka 
Published: October 2002

The rotator phase transitions in odd n-alkanes, n-C21H44 and n-C25H52, were investigated by optical microscopy. On cooling an n-C25H52 single crystal, a new transient intermediate state was observed within 1/30 s between the rotator phase (RV) and the low-temperature phase (IV). The rotator phase transition in n-C25H52 proceeds through two successive structural changes: uprighting of molecules and ordering of side packing. The two-stage changes on cooling were found to be peculiar to the transition accompanied by the molecular tilting motion, such as the RV→IV transition in n-C25H52. In contrast, in n-C21H44, the intermediate state was not observed.
Optical Properties and EL Characteristics of Poly[(disilanylene)oligophenylenes]
Authors: Katsumi Yoshino Katsumi Yoshino , Kazuhisa Hosoda Kazuhisa Hosoda , Akihiko Fujii Akihiko Fujii , Mitsuo Ishikawa Mitsuo Ishikawa 
Published: October 2002

Band-gap energies of poly[(disilanylene)terphenylene] (PDSiTP) and poly[(disilanylene)quaterphenylene] (PDSiQP) films have been evaluated as 3.5 eV and 3.3 eV, respectively, which are similar to those of p-terphenyl and p-quaterphenyl films. Contrary to poly(methylpropylsilane), large Stokes shift of photoluminescence (PL) is observed in these polymers, which is similar to the cases of p-terphenyl and p-quaterphenyl. Blue electroluminescence (EL) has been observed in diodes of MgAg/PDSiTP/ITO and MgAg/PDSiQP/ITO structures with peaks at 440 nm and 443 nm, respectively. These polymers are much more stable than poly(methylpropylsilane) under ultraviolet light irradiation.