bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption of CO, O2 and CO2 on Titanium Film by Electrical Conductivity Measurements
Authors: Kawasaki Koji , Hayashi Nobuyuki , Ebisawa Shigeo , Sugita Toshio
Published: November 2005

The variation in the electrical resistance of titanium film due to the adsorption of such gases as carbon monoxide and oxygen is measured to make clear the binding states of adsorbed gases through the electronic interaction.
Furthermore, the adsorption of carbon dioxide on clean film of titanium at room temperature is studied by means of mass spectrometry and by measuring simultaneously electrical resistance.
From these measurements, it is considered that CO2 is dissociated into CO and O on titanium film and CO formed by the dissociation has two different binding states of adsorption on the film.
High Electron Mobility InSb Films Prepared by Source-Temperature-Programed Evaporation Method
Authors: Ohshita Masahide
Published: November 2005

InSb thin films are prepared by a source-temperature-programed evaporation method to reduce imperfections of crystal structure, and their crystalline and electrical properties are studied.
An optimum source temperature program is investigated to obtain an appropriate source material composition. Films thus prepared has an electron mobility of 61,000 cm2/V·sec at room temperature and a donor concentration of 3.5×1015/cm3. An X-ray analysis of the film showes a high degree of stoichiometry.
Effect of Anisotropic Stress on Random Anisotropy in Ferromagnetic Thin Films
Authors: Fujii Toshitaka , Tanaka Toshihiko , Uchiyama Susumu , Sakaki Yoneichiro
Published: November 2005

The generalization of Doyle-Finnegan's theory on the effective magneto-crystalline anisotropy (or the random anisotropy) in polycrystalline ferromagnetic films is presented taking account of the anisotropic stress in the film. The effect of the anisotropic stress is found to be significant only around the composition of λ100=λ111≠0, where λ100 and λ111 are the magnetostriction constants. Assuming that the anisotropic stress is five percent of the isotropic one independent of the film composition and the annealing, this extended theory is compared with the experimental result, where the random anisotropy is estimated from the fall back angle measured for evaporated Ni–Fe films. The agreement between this calculated result and the experimental one is satisfactory over whole composition range of the experiment from 50% to 95% Ni.
Preparation and Electrical Properties of GaSb-Ge Heterojunctions by Vapor Growth Technique
Authors: Ido Toshiyuki , Kakehi Masahiro , Arizumi Tetsuya
Published: November 2005

GaSb-Ge heterojunctions having a large lattice misfit (8%) are fabricated by a conventional closed tube process in which Ge (p- and n-type) and SbCl5 used as a substrate and a transport agent, respectively. The substrate and source temperatures are ranged from 600°C to 650°C and from 650°C to 675°C, respectively. The epitaxial layer of GaSb is a p-type single crystal, so a pGaSb–nGe structure is obtained if n-Ge is used as a substrate. When the substrate is p-Ge, Sb diffused into the Ge to produce a pGaSb–nGe–pGe structure during the deposition. The V–I characteristics of these heterojunctions are explained satisfactorily on the basis of the Riben's multi-step tunneling model.
Highly Stabilized Time Mode Mössbauer Spectrometer Employing Crystal Controlled Digital Circuits
Authors: Miyajima Hideki
Published: November 2005

A time mode Mössbauer spectrometer is constructed so as to get a well resolved spectrum. All the pulses used in the apparatus are generated by the digital circuits, which are triggered with the highly stable crystal oscillator. The operation is stable for a long run. Absorption peaks are well resolved and signal to noise ratio is improved.
Thermal Effect of Ultrasonic Vibration of Quartz Crystal Microbalance on Chemical Reactions
Authors: Shiojiri Makoto , Hasegawa Yasuo , Tsujikura Yozo
Published: November 2005

Weight gains due to the reaction of iodine vapor with vacuum-deposited silver films have been measured by a quartz crystal microbalance operated at different crystal exciting powers. The reaction rate is found to decreases with increasing exciting power of the crystal. This is explained as the result of increase of reaction temperature from an observation that the rate of this reaction decreases with increasing temperature. The increase of temperature is measured directly, by using thermocouples made by vacuum-deposition of copper and constantan on the crystal, to be about 17°C and 0.1°C at the exciting powers of 300 mW and 5 mW in a vacuum. It is concluded that the quartz crystal microbalance can be used without the thermal influence of the vibration for the measurement of weight changes of such reactions as far as it was operated at exciting power as weak as 5 mW.
Cu K X-Ray Absorption Spectra and Coordinations of Some Cu(I) and Cu(II) Compounds
Authors: Obashi Masayoshi , Nakamura Toshiko
Published: November 2005

The fine structures of X-ray K absorption spectra of copper in CU2O, KCu(CN)2, CuCl, CuO and Cu(NH3)4SO4·H2O, KCuF3 and Cu(CH3COO)2·H2O, CuI(bipy)2·ClO4, and Cu(acac) (OH2)2·P, having linear, trigonal planar, tetrahedral, square planar, distorted octahedral, trigonal bipyramidal and square pyramidal coordinations respectively, are photographed by a bent crystal spectrograph of Cauchois type. The compounds CU2O, KCu(CN)2, CuCl and KCuF3 have typical fine structures which are different from each other. The fine structures of CuO, Cu(NH3)4SO4·H2O, KCuF3, Cu(CH3COO)2·H2O, CuI(bipy)2·ClO4 and Cu(acac) (OH2)2·P nearly coincide with each other. The arrangements of atoms around each copper atom in these six substances may be considered as a single distorted octahedral sphere, and their coordinations are not the same type. It is accordingly concluded that the fine structure is mainly determined by the immediate surroundings of the atom in question in a region up to about 100eV from the main edge.
Correlations of Acoustoelectric Instabilities with Inhomogeneities in CdS Measured by Optical Probe
Authors: Yamada Masayoshi , Hamaguchi Chihiro , Nakai Junkichi
Published: November 2005

In order to correlate some aspects of the acoustoelectric instabilities with the sample inhomogeneites, the internal inhomogeneity in resistivity profile in semiconductive CdS single crystals is measured by means of an optical probe, utilizing the local photo-conductance produced by the projection of a laminar light beam through the sample. Results indicate marked inhomogeneities. Several aspects of the acoustoelectric instabilities are found to be related to the variation in resistivity of a sample, i.e., there occurs moving domain and pinned domain depending upon the resistivity profile. The presence of a somewhat higher resistance region, near the cathode where acoustoelectric gain is higher, induces easily the moving domain. On the contrary, if there is such a high resistance region near the anode, the domain is pinned there without its destruction.
Preparation of Samarium Cobalt Permanent Magnet by Compacting with Solid Pressure Media
Authors: Umebayashi Hiromichi , Fujimura Yasuo
Published: November 2005

A new modification of the preparing method of SmCo5 permanent magnets is studied. The method involves compacting the field-oriented pellet of the alloy powder through a solid state pressure transmitting medium in a conventional axial pressing apparatus. Zinc and calcium stearates have proved to give very satisfactory results as pressure media up to 30 kbar. Permanent magnets with (B
H)max of 15 MGOe is obtained.
It is found that an essential improvement of the particle alignment is achieved in the field-orienting process when the powder is pressed in the perpendicular, rather than parallel, direction to the magnetic field.
Long term aging experiments of epoxy-bonded magnets are conducted and no change of B
r and 1
H
c has been found in 15,000 hours at room temperature and 1,500 hours at 50°C.
A Synchronized Rapid-Scanning Multi-Channel Spectrometer
Authors: Urano Yoshio , Kosasa Kyoko , Maruyama Yoshio
Published: November 2005

A rotating mirror driven by a current pulse is combined with a multi-channel spectrometer to enable a rapid scanning of spectra. The speed and range of its wavelength scan are 0.6 Å/µsec and 80 Å respectively, using a spectrometer of dispersion of about 5 Å/mm. The rotating mirror effectively changes the position of the virtual entrance slit, and a wave-length scanning can be done at the exit slits which are fixed on the Rowland circle.
The current pulse which drives the rotating mirror can be triggered from, and so the scanning can be synchronized with, the phenomenon to be observed. A device which gives a wave-length scale on an oscilloscope trace of the scanned spectrum is also included.
A Digital Gate Unit for Multiparameter Pulse Height Analysis
Authors: Adachi Minoru , Fujioka Manabu , Taketani Hiroshi , Hisatake Kazuo , Okuhara Hiroo
Published: November 2005

A new digital gate unit for multiparameter pulse height analysis is described. The 3-bit comparator which is used to select gate segments in the digital gate unit is described in detail. Performance of this unit in the case of a gamma-gamma coincidence measurement with Ge(Li)-NaI(T1) detectors is also presented.
Slow Plastic Flow of a Bingham Material Between Rotating Concentric Infinite Cylinders with Axial Roughness
Authors: Batra R. L.
Published: November 2005

In this paper slow plastic flow of a Bingham solid between rotating concentric infinite cylinders with axial roughness is investigated. The effects of cylinder perturbation on the velocity distribution are determined. Sinusoidal roughness given by ε
N
1(z)=h
1sin
(2πz/λ1) and ε
N
2(z)=h
2sin
(2πz/λ2), where ε is the small parameter of the boundary perturbation, is considered as an illustration. Two special cases of practical importance are studied. In the first, the roughness wave-lengths are large as compared to the radii of the cylinders and in the second, spacing between the cylinders is taken small. The average moment per unit length on the cylinders is calculated and the order of perturbation in the moment is dermined. By taking h
1=h
2=10-3 cm, b-a=10-2 cm and a=1 cm, the moment M2 on the outer cylinder has been calculated and compared with the moment M
0, when the cylinders are taken smooth. For Bingham number equal to 0,1,2 the ratio (M2-M
0)/M
0 is determined for various values of λ2/λ1, the ratio of wavelengths. It is found that, with the increase of Bingham number, the value (M
2-M
0)M
0 increases for λ2/λ1>1 for the considered cases.
Magnetic Domain Walls in Zone Melted Iron Crystals as Observed by X-Ray Diffraction Topography
Authors: Yamashita Tadayoshi , Mihara Akira
Published: November 2005

Thin iron crystals having the (001) plane parallel to their surfaces are prepared from zone melted iron, and 90° magnetic domain walls and black-white images appearing at the junctions of {110} 90° walls are examined by transmission X-ray topography. The topographs are taken with various reflections. The displacement of lattice points in the neighbourhood of a {110} 90° wall is in the planes parallel to the wall plane. Black-white images are formed by axially symmetrical strain fields around the junctions of {110} 90° walls. Long straight images lying in the <100> directions in the crystal surfaces and short images in rows in the <100> directions are found. These images are due to the strain fields around the junctions, having the <100> directions, in the interior of the crystals.
The strain fields giving rise to the black-white images are discussed in terms of the dynamical theory of diffraction contrast in deformed crystals.
Electrical and Optical Properties of GaSe
Authors: Tatsuyama Chiei , Hamaguchi Chihiro , Tomita Hiroshi , Nakai Junkichi
Published: November 2005

Absorption, photoconductivity, resistivity, and Hall coefficient of GaSe are measured. The photoconductivity spectrum reflects the exciton absortion. The crystal is p-type with two activation energies, of which value is about 0.26 eV above 200°K and 0.12 eV below 200°K for one specimen. Temperature dependence of the mobility is given by µ∝T
-n
, where n is about 2. Ratio of the resistivity perpendicular to the layers to parallel one is about 10∼50. The activation energy almost equal for both orientations. Electric field dependence of the conductivity perpendicular to the layers is explained by an “anomalous” Poole-Frenkel effect. Estimated dielectric constant is ε=5.7 at 293°K and 6.6 at 102°K.
Electrophoresis Diffusion Equilibrium –A New Method for Measuring the Charge of Polyelectrolytes–
Authors: Yoshida Mizuki , Miduno Zen'emon
Published: November 2005

A new method termed “Electrophoresis Diffusion Equilibrium”, which enable direct determination of the charge of polyelectrolytes, has been developed. In this article the principle of this method and the time required to determine the charge of polyelectrolytes are discussed and the schematic diagram of this apparatus is shown. The charge of Potassium Polyvinyl Alcohol Sulfate (PVS-K) is determined in Miller and Golder's buffer with pH=7.00 and the ionic strength I=0.20. The value of the charge obtained by this method agrees with the result obtained by electrophoresis and diffusion method.
Surface Smoothness and Lattice Constant of Gallium Arsenide Grown by Liquid Phase Epitaxy
Authors: Maruyama Susumu
Published: November 2005

Layers of GaAs are grown on the (100) plane of GaAs substrates under various growth conditions of liquid phase epitaxy. Two kinds of surface are observed. The one has mosaic surface structure and is cloudy, the other has wavy surface structure and is mirror-like. The lattice constants of epitaxial layer and the substrate (undeposited side) have been determined precisely by the Bond method. When the lattice constant of epitaxial layer differs from that of substrate, the wafer is bent in the side of the smaller lattice constant. An epitaxial layer grown on the unbent substrate or the convex side of bent substrate has mosaic surface structure. On the other hand a wavy surface layer grows on the concave side of bent substrate. The bending is caused by clamping and heating the wafer during the growth experiment.
Properties of a New Avalanche Diode Oscillator Computed by a Large-Signal, Self-Consistent Simulation
Authors: Kawarada Kuniyasu , Mizushima Yoshihiko
Published: November 2005

An analog simulation technique is applied to a large-signal analysis of a new type of an avalanche diode oscillator by considering the effects of the external circuit. To utilize the field variation due to the space-charge accumulation of the avalanche-multiplied carriers, a diode having double-peaks in its internal fiield distribution is proposed.
The results of the simulation show that a new diode can operate with a high-efficiency under the resistive load as well as under the resonant circuit load. Also a new application in high-speed pulse circuits is expected from the pulse response characteristics. Effects of the external circuit conditions such as the impedance matching and the second harmonic tuning are studied. An injection-locking phenomenon is also simulated. These findings of characteristic features show the inherent advantage of the self-consistent analog-simulation method.
Modified Luneburg Apodization Problem I
Authors: Kusakawa Tohru
Published: November 2005

One of the modified Luneburg apodization problems suggested by Wilkins as an unsolved apodization problem is solved in this paper. The problem is to find the pupil function which maximizes the total flux inside a prespecified circle in the Fraunhofer diffraction image plane, subject to the conditions that the pupil function satisfies the inequality |T(r)|≤1 and that the total flux passing the aperture is specified to have a certain value. The method used is the calculus of variations leading to a nonlinear integral equation which is solved by successive approximations using the dummy functions. The resultant pupil functions obtained are compared with those obtained by Straubel and Lansraux and Boivin.
DC Characteristics of Electroluminescent Evaporated ZnS:Mn, Cu, Cl Films
Authors: Plumb John L.
Published: November 2005

Electroluminescent cells are prepared by evaporation of ZnS:Mn, Cu, Cl onto tin oxide-coated glass substrates, subsequent heat treatment at greater than 600°C, evaporation of an Al electrode, and finally complete forming by application of positive voltage to the Al electrode. There is an indication that after deposition the Cu concentration is higher adjacent to the substrate, and that Cu is redistributed by the heat treatment. Forming occurred also, if an oxide film is deposited before the Al. It is likely that Cu ions drift during forming causing shorting paths of Cu to be opened near the Al electrode. The presence of a high resistance layer between the Cu and Al is required to initiate the migration of Cu. An exp √V dependence of current on voltage is found, suggesting Schottky emission of electrons from Cu to ZnS. The ratio of brightness to current exhibits an exp √1/V dependence on voltage.
Characteristics of Link-Type Cubic Anvil, High Pressure-High Temperature Apparatus
Authors: Wakatsuki Masao , Ichinose Kazuaki , Aoki Toshio
Published: November 2005

Operational characteristics are investigated for evaluation and improvement of a high pressure apparatus which has a new anvil-driving mechanism. Analysis and measurement of anvil motion reveales that a very accurate anvil-alignment is achieved and maintained throughout hundreds of usages. Pressures are generated up to 100 kbar with avils having square faces 10 mm on an edge, and 120 kbar with anvils having square faces 6.4 mm on an edge. A method is devised to correct the effect of elastic deformation in structural parts, and completely isotropic compression is realized. Temperatures higher than 2000°C are attained in samples, 4 mm in diameter and 8 mm in length, while anvil-temperatures do not exceed 300°C. Operational ease and long anvil-life in the apparatus are attributed to the new anvil driving mechanism.
Low Temperature Specific Heats of Pure Zinc
Authors: Mizutani Uichiro
Published: November 2005

Specific heat of pure zinc has been measured in the temperature range of 1.7 to 4.2°K. The electronic specific heat coefficient γ and the Debye temperature \varTheta0

c
are determined by means of a least squares fit as (0.633±0.002) mJ/mol. deg2 and (319.7±1.0)°K, respectively. The present result shows an appreciable deviation from a straight line if it is plotted in C/T vs. T
2 diagram, indicating that the T
5 term cannot be neglected. The present data of \varTheta0

c
, in particular, are discussed in connection with the elastic Debye temperature \varTheta0

c
.
Superconducting Transition Temperatures of R. F. Sputtered NbN Films
Authors: Keskar K. S. , Yamashita Tsutomu , Onodera Yutaka
Published: November 2005

NbN films are examined with respect to their electrical and superconducting properties. The films are deposited by r.f. reactive sputtering technique under argon gas atmosphere added with nitrogen. The films obtained have a wide range of resistivities and transition temperatures depending upon the partial nitrogen pressure in the argon atmosphere and the substrate temperature at which the films were deposited. The maximum transition temperature obtained is 17.3°K, higher by 0.9°K than the highest one reported so far.
Vapor Transport of Gallium in the Ga-PCl3-H2 System
Authors: Seki Hisashi , Eguchi Hiroshi , Gejyo Tetsuo
Published: November 2005

A theoretical consideration based on thermodynamics has been developed and the result is compared with experimental results obtained for the transport of gallium. The transport rate of gallium is discussed as a function of the reaction temperature, the hydrogen flow rate and the mole ratio of Cl/H. A good agreement is found between the theory and experimental results.
It is also shown that the experimental data of Luther and Roccasecca are predicted by the theory and that the theoretical results give an upper limit of the transport rate of the gallium.
Absorption Kinetics of Nitrogen+Tantalum System
Authors: Yamazaki Hisashi
Published: November 2005

The dependence of the absorption rate on temperature is studied for a single-crystal tantalum wire, and is compared with those for polycrystal wires and ribbons.
Two processes of absorption of nitrogen in tantalum are found. In the first process absorption occurs at boundaries of crystal grains and is observed for polycrystal ribbons with surface of the (311) planes; the activation energy of absorption is 1.9 eV/2-atoms. The second process is observed for crystallized or sufficiently flashed wires. In this process atoms chemisorbed on the surface are directly absorbed into the bulk at their absorption sites; the activation energy of absorption is 4.0 eV/2-atoms, which is larger than that of diffusion of nitrogen in tantalum.
Field Dependence of Magnetoresistance in No-binder Soft Carbons at 77°K
Authors: Hishiyama Yoshihiro , Ono Akio , Hashimoto Masaaki
Published: November 2005

The dependence of magnetoresistance on magnetic field is investigated at 77°K for soft carbons prepared from Texas petroleum coke (no-binder) by heat treatments in the range 1400°–3000°C. For specimens heat treated at temperatures between 1400° and 2200°C, the magnetoresistance is negative; its absolute value increases monotonically with increasing heat treatment temperature (HTT) and with increasing magnetic field. For specimens heat treated between 2400° and 2450°C, the magnetoresistance is negative and tends to saturate at higher fields. The absolute value becomes larger for lower HTT. Specimens heat treated between 2400° and 2450°C show a magnetoresistance which is negative at low fields, passes through minimum and becomes greater for lower HTT. For specimens with HTT≥2570°C, no negative magnetoresistance is observed even at low fields. Some discussion of the effects found is included.
Critical Switching Curve and Hysteresis Loop Due to Fanning Spin Structure in a Thin Magnetic Film
Authors: Imamura Nobutake , Hayashi Nobuo
Published: November 2005

New critical curves and hysteresis loops for a single layer magnetic thin film are calculated on a rectangular coordinate (H

x
, H

i
). H

i
is the inhomogeneous internal field caused by the current passed through the film and H

x
is the field parallel to the easy direction of magnetization. In this case direction of the spins varies within the film plane, and the single domain model cannot be used. The film is divided into multi-layers and the spin distribution is solved numerically using the variational method. It is shown that there exists a region where the fan-shaped spin configuration like the Bloch wall twists by more than 180 degree, and also that the critical switching curves change severely with the film thichness.
A High Temperature X-Ray Diffractometer Using a Solar Furnace
Authors: Kamada Osamu , Takizawa Tsuyoshi , Sakurai Takemaro
Published: November 2005

Using a solar furnace, 10 m in aperture and 3.2 m in focal length, a high temperature X-ray diffractometer is constructed. By this apparatus, the thermal expansion of CaO was measured up to 2150°C.
The f(χ)-Curves for FeKα and AlKα X-Rays in the Inclined EPMA Targets of Fe, Al and Fe-Al Alloy
Authors: Gennai Norio , Murata Kenji , Shimizu Ryuichi
Published: November 2005

The rotaing inclined target method is applied to obtain thef(χ)-curves for pure iron, pure aluminum and Fe–Al 24.09 wt% alloy targets mounted in electron probe micro-analyser (EPMA). Some considerations on experimental arrangement for accurate measurement are described. Obtainedf(χ)-curves are applied to the quantitative micro-analysis of Fe–Al alloy, and the results are confirmed to agree with chemical analysis.
Ultrasonic Birefringence in a Rheological Body under Initial Stress
Authors: Kuo Hung Liang , Takizawa Éi-Iti , Doi Tosiaki
Published: November 2005

Calculations are made on velocities and damping coefficients of longitudinal and transverse ultrasonic waves in a visco-elastic body under initial stress. Plots of wave-velocities and damping coefficients versus wave-frequency are given. Phase-differences between two differently polarized transverse waves are also calculated. For small extra shearing rigidity and small initial stresses, the phase-difference is proportional to the product of wave-frequency and the difference in initial stresses. Briefly mentioned is the so-called acousto-viscoelastic method for measuring stress, which is quite analogous to photo-elastic one.
The In-Ga-P Ternary Phase Diagram
Authors: Kajiyama Kenji
Published: November 2005

The In–Ga–P ternary phase diagram has been calculated in the regular solution approximation. The calculated result is in agreement with experiments. The bandgap energy of In
x
Ga1-x
P is also determined experimentally.
Numerical Solutions of Basic Equations of Dissociative Diffusion
Authors: Yoshida Masayuki , Kimura Ken
Published: November 2005

Basic equations of dissociative diffusion are non-linear. Their solutions are obtained numerically for three cases of gold in silicon. Approximate solutions are also obtained analytically by assuming that interstitial gold is in thermal equilibrium on the basis of the criterion for the assumption proposed previously by one of the authors. It is found that the numerical solution for interstitial gold reaches the thermal equilibrium value most rapidly and that the numerical solutions for substitutional gold and vacancy agree with the approximate solutions for them after interstitial gold reaches the thermal equilibrium value. It is also found that the experimental result of the rapid increase of substitutional gold at the beginning of diffusion of gold can not be explained by the numerical solution.
Decrement of Piezoelectric Constants Caused by Screening Effect of Conduction Electrons on the Effective Charge of CdS Crystals
Authors: Ogawa Tomoya , Oikawa Hideo , Kojima Akira
Published: November 2005

Decrement of piezoelectric constants in n-CdS crystals is observed as a function of conductivity. The decrement of the constants is closely related to the increment of the electrical conductivity with a one-valued function in a range between 10-8 and 10 ohm-1 cm-1. For example, the piezoelectric constant in a CdS crystal with 10 ohm-1 cm-1 is only 40% of that with 10-8 ohm-1 cm-1.
This phenomenon is theoretically explained by the decrement of the effective charge on Cd or S ions caused by the Thomas-Fermi screening of conduction electrons in n-CdS crystals.
Optical Transmission in an Excited Two-Level Medium
Authors: Ohtsuka Yoshihiro
Published: November 2005

Transmission characteristics in an excited absorbing medium are discussed on the basis of the photon transport-equation and the rate equations. An increasing power of the C
W laser beam passing through the medium is considered when this medium is excited at the same time by a different pulse of radiation. A typical example of a square excitation-pulse states that the transmittance recovers to its original value after it once reaches a maximum value. The time response of the medium depends upon the total number of absorbing centers M, the absorption cross-section σ, and the relaxation time τ as well as the intensity of radiation sources I. The decay time of the increased transmittance is proportional to τ/σM if the quantity (1-M/2τI) is kept constant. As a numerical example the relaxation time of SF6 is estimated to be 2×10-6 s at a pressure of 3.7 Torr in comparison with an experimental result.
The Nature of Defects in Quenched α-Brass
Authors: Yamaguchi Hiroyuki , Hashimoto Iwao , Yoshida Sho
Published: November 2005

The defects such as faulted dislocation loops, perfect dislocation loops and stacking-fault tetrahedra are observed in quenched α-brass. The faulted loops lie on the {111} planes and have various polygonal shapes with edges along the <110> directions. The perfect loops have hexagonal, rhombic and irregular shapes, and the former two are on the {111} planes with their edges along the <110> directions. Analysis of the image contrast reveals that the faulted loops are of the vacancy type having a Burgers vector a/3<111> and the perfect loops are of the vacancy type having a Burgers vector a/2<110>. The perfect loops are favoured when the quenching temperature is high, while the faulted loops are favoured when the temperature is low. The stacking-fault tetrahedra are occasionally observed by high temperature quenching. The formation energy of a vacancy is estimated to be about (1.00±0.05) eV from the density and size of observed loops. The formation of three different defects is discussed by the simple energy comparison.
On the Crystal Structure of MnAl(r) Phase
Authors: Yoshida Kentaro , Nagata Saburo
Published: November 2005

MnAl(r) phase is investigated by both X-ray powder method and transmission electron microscopy. The unit cell is concluded to have “body-centred rhombohedral” symmetry, with lattice constants of a=8.96 Å and α=89° 1' when the alloy has composition of 43 at. per cent of manganese. Single crystalline electron diffraction patterns also assure this unit cell. Surface etching patterns of the alloy, which often look like arrow feathered patterns, are also observed on transmission electron micrographs. The micro-structure can be interpreted on the basis of above cell and a model of configuration of the subgrains is proposed, boundaries of which, shafts and barbs, are indexed as {100} and {110} respectively.
Solutions of Modified Heat Equation by Electric Analogy
Authors: Etori Kanji
Published: November 2005

Predicting the finite velocity of propagation of thermal impulses, general modification of linear heat equation in Fourier theory is expressed by electric analogy.
Each solution of the modified heat equation, which is obtained by each condition of the input of sinusoidal temperature wave and of heat pulse at the boundary surface, corresponds to the conventional one used in the theory of the measurement of thermal properties and in the source theory of diffusion, respectively.
Nonohmic Properties of Zinc Oxide Ceramics
Authors: Matsuoka Michio
Published: November 2005

Nonohmic properties of ZnO ceramics with five additives of Bi2O3, CoO, MnO, Cr2O3, and Sb2O3 are studied in relation to sintering temperature, additive content, and temperature dependence. The observation of electron photomicrographs and X-ray microanalysis proves a ceramic microstructure such that ZnO and these five oxides form, at the grain boundaries, segregation layers which are responsible for the nonohmic properties. The electrical resistivity and dielectric constant of segregation layers are estimated to be 1013 ohm-cm, and 170, respectively by using a simple model. The electric field strength corresponding to the steep rise in the current is also estimated to be 104 V/cm by taking account of the concentration of applied voltage at the segregation layer. In view of these data and simple model, a possible explanation for nonohmic properties is discussed.
Vacuum-Arc Evaporations of Ferrites and Compositions of Their Deposits
Authors: Naoe Masahiko , Yamanaka Shunichi
Published: November 2005

The evaporation in a vacuum of the order of 10-4 torr with a current of 14 A is investigated by electron-microscopic observation of the surface of the ferrite source, spectroscopic analysis of the vapour emission and composition analysis of the discharge atmosphere. Ferrite is thermally decomposed to release oxygen gas in the region of cathode spots. Most of the constituent metals are evaporated in the state of atom. The difference in cation ratio Me/Fe between the source and its deposit is rather small, where Me is one of Mg, Mn, Co, Ni, Cu and Zn. The evaporation rate of each metal depends on the temperature at which its vapour pressure is 10-2 torr. If the source composition is carefully controlled, it is possible to make the cation ratio of its deposit adequate for typical simple ferrites, and even mixed ferrites, such as Ni0.3Zn0.7Fe2O4 and (N0.85Cu0.15)0.94Fe2.06O4.
Fabry-Perot Resonator with Circular Apertures
Authors: Yoshida Yasuo , Ogura Hisanao , Ikenoue Jun-ichi
Published: November 2005

A resonator with circular apertures at the centers of the parallel-plane circular mirrors is studied. The approach is a modification of the foregoing analysis by the authors. The mode and the diffraction loss are obtained from the complex-frequency which gives a source-free field distribution. The loss is represented in terms of the Fresnel numbers of the mirrors and the apertures. The field distributions are calculated for the several lowest-order modes. The loss of a resonator with infinite strip mirrors is derived from the limiting case of the above result. Furthermore, the diffraction loss of a resonator with a single aperture is also obtained, which gives an increase of about 20 percent compared with the case of two apertures.
A Scanning Electron Microscopic Method of Obtaining Electric Field Distributions Using Solid-State Models
Authors: Munakata Chusuke
Published: November 2005

Al-electrodes are evaporated upon a 5 \varOmegacmp-type Si wafer to make solid-state models for a triode, a hairpin-type electron gun, and a pair of electrodes. Each model is 0.3 mm thick, 4 mm square, and mounted on a TO-5 header. Each model is irradiated with an electron beam pulsed at a 100 kHz rate whose energy, current and diameter were 22 keV, a few nA and about 1 µm, respectively. Scanning electron microscopic images of the electric field distribution are obtained by using the β-conductive signal under various biasing conditions of the models to demonstrate the validity of the present method. The results were, however, disturbed by an abnormal edge effect due to the evaporated metal-electrode.
The Influence of Moisture on the Storage Phenomenon in As2Se3Evaporated Films
Authors: Utsumi Nobutaka , Wada Masanobu
Published: November 2005

The influence of moisture on the persistence of photoconduction has been investigated on sandwich type cells with an evaporated As2Se3film and two evaporated Al electrodes. While the phenomenon is observed in the cells prepared by moisture-free processes, no storage is observed in the cells with theelectrodes containing adsorbed water. Thus water is shown to plays an important role in the disappearance of the storage phenomenon.
Electrical Conduction in Tetragonally Distorted Manganite Spinels
Authors: Kshirsagar S. T. , Sabane C. D.
Published: November 2005

The compounds with spinel lattice structure (1) Cd
x
Cu1-x
Mn2O4, (2) Co
x
Cu1-x
Mn2O4 and (3) Mg
x
Cu1-x
Mn2O4 (0≤x≤1) are prepared. Studies of crystal symmetry as a function of composition and of electrical resistivity as a function of composition and temperature, are reported. The compositions with tetragonal symmetry exhibit thermal hysteresis of electrical resistivity, whereas those with cubic symmetry display usual linear variation of log
ρ vs. 1/T. The electrical conduction involves the hopping mechanism of electrons between octahedral site Mn3+ and M4+ ions. It is shown that there is major contribution to activation energy due to the cooperative distorting forces in the tetragonally crystallized systems. CuMn2O4 is shown to have cation distribution

Cu
z

1+Cu1-z

2+[Mn
z

4+Mn2-2z

3+]O4
2-

where (0<z<0.1).
Relative Integrated Intensity of the X-Ray Diffraction and Effective Charge in GaAs1-xPx Compounds
Authors: Osamura Kozo , Murakami Yotaro
Published: November 2005

An X-ray study with CuKα is carried out on fine-powder samples of GaP, GaAs and their quasi-binary compounds. Integrated intensities of 14 lines from the (111) to the (533) are measured on a relative scale. The temperature factors of individual atoms are determined by the condition of minimizing the R-factor. The assumption that the atomic scattering factor of the group V atom in the quasi-binary compounds is represented by a linear combination of constituent group V atoms is shown to be valid from the experimental analysis. The variation of the effective charge in the GaAs-GaP quasi-binary system is estimated in three ways. The fact that negative charge is transferred from the group III atom to the group V atom is concluded in GaP, GaAs and their quasi-binary compounds.
Shift of the Gate Threshold Voltage of MOS Transistors dne to the Introduction of Shallow Impurities
Authors: Tanaka Toshio
Published: November 2005

It is possible to shift the gate threshold voltage of MOS transistors with little sacrifice of other device performances by introducing shallow level impurities only into a region near the semiconductor surface under the gate. Some theoretical information is given which may be useful for designing MOS transistors in an attempt to realize such a shift. The effects of the impurity introduction on the characteristics of MOS diode structures are also described.
Equilibrium Computation for the Growth of Alpha Silicon Carbide from Silane and Propane in the Presence of Hydrogen or an Inert Gas
Authors: Minagawa Shigekazu , Gatos Harry C.
Published: November 2005

The equilibrium computation for the growth of α-SiC from silane and propane in an atmosphere of hydrogen or an inert gas is carried out. The dependence of the deposition ratios of α-SiC, Si(l) and C(graphite) and the partial pressures of the vapor species on the concentration of the reactants and on the temperature is analyzed in detail. It is shown that in hydrogen atmosphere the deposition of α-SiC single phase occurs over a wide range of reactant partial pressures, i.e., from P(SiH4)=3×P(C3H8) to a significant propane excess. In the presence of an inert gas this range is limited to the vicinity of P(SiH4)=3×P(C3H8). This difference is apparently attributed to that the inert gas cannot remove the excess carbon into the vapor phase. Additional thermodynamic characteristics of these systems are also discussed.
Broadening of Landau Levels in Two-Dimensional Electron Gas: Its Effect on Surface Capacitance
Authors: Ohta Kuniichi
Published: November 2005

Based on effective mass theory, broadening of Landau levels in two dimensional electron gas is obtained bar taking account of multiple scattering due to impurities. Using the diagram technique, one particle Green's function is derived and it is shown that the physical origin of the level broadening is characteristic of two dimensional electron gas. Using the Green's function, the notches occuring in capacitance-voltage characteristics at low temperatures are qualitatively discussed in terms of the broadening of Landau levels. The implication of this broadening of Landau levels is discussed in relation to transport phenomena of two dimensional electron gas in strong magnetic fields.
Electrical Properties of CuI Thin Films
Authors: Kokubun Yoshihiro , Watanabe Hideo , Wada Masanobu
Published: November 2005

Hole concentration of CuI thin film decreased but Hall mobility increased with the rise of reaction temperature of copper films with iodine vapor. The heat-treatment of CuI film in vacuum brings out the decrease of hole concentration because of the escape of excess iodine from the film.
Oxygen diffuses into the bulk of Cut film at high temperatures and raises the conductance of the film. The activation energy for diffusion was determined as 0.82 eV. Water vapor is chemisorbed on the surface of CuI and lowers the conductance at room temperature.
Piezoresistance Effect of Graphite-Papostor1)
Authors: Ohe Kazuyuki , Naito Yoshihide
Published: November 2005

A large response of electric resistance to hydrostatic pressure is observed in graphite-papostor (the mixture of graphite, paraffin and polyethylene). The piezoresistance coefficient is -1700∼-2800×10-12 cm2/dyne under a hydrostatic pressure of 0∼700 kg/cm2. This coefficient is comparable with those of some organometallic compounds.
The piezoresistance coefficient under uniaxial compression is positive and its characteristics are essentially different from those of the coefficient under hydrostatic pressure.
Study on the Flux Reversal of Ferrite Cores
Authors: Hasegawa Masahiko
Published: November 2005

Switching behaviour of ferrite cores is investigated. The linear relationship between ln
ln
(I

r
/(I

r
-I)) and ln t is found. To describe this property, nucleation and subsequent growth processes of reversed magnetic domains are discussed.
Flux reversal consists of two processes, i.e., the nucleation process of reversed domains and the growth process of nucleated reversed domains. The nucleation process can be divided into two cases; athermal nucleation and thermal nucleation. In the earlier stage of flux reversal, the nucleation process is dominantly athermal and in the later stage, thermal nucleation process dominates.
The density of nucleation centers of previously existing reversed domains is estimated as about 3.0×108/cm3 and this means one nucleation per each grain or two.
A Multichannel System for Determination of Time Varying Spectral Line Profiles
Authors: Okazaki Kiyohiko , Andō Kōzō , Mori Kazuo , Okamoto Kosuke
Published: November 2005

An instrument has been constructed which can directly display on an oscilloscope time-resolved profiles of a spectral line emitted from a transient plasma. It has closely spaced 17 optical channels, and the wavelength coverage between the outermost channels can be varied from 10.4 to about 0.8Å by the proper choice of a grating and a magnifying cylindrical lens. Profile measurements can automatically be repeated with time resolution from 0.1 to 2 µs. The display of these time-resolved line profiles has been accomplished by means of electronic circuit. An example of application to a transient plasma is shown.
Reflection from Anode Side and Decay of High Field Domain in Semiconducting CdS
Authors: Fukui Masuo , Uchida Yukimasa , Arizumi Tetsuya
Published: November 2005

Acoustic domains in semiconducting CdS are observed by means of 2-finger potential probe method. Suggestions by Many and Balberg that domains are reflected from the anode in the case of damped current oscillations but they are not reflected in continuous current oscillations are confirmed. The domain measurements were made.
The reversal of the polarity of the domain field is also observed when the voltage pulse is terminated before the high field domain reached the anode. The decay mechanism of the reversed domains is discussed. The result indicates that the reversed domains decay through the linear electronic loss and the linear nonelectronic loss. With increasing the applied electric field the frequency of the amplified acoustic flux shifts to the lower side.
Schottky Probe as a Diagnostic Tool for Dynamic Solid-Plasma Phenomena
Authors: Ueno Isao , Tanimoto Mitsumori , Sekiguchi Tadashi
Published: November 2005

The Schottky probe, in place of n
+-probes conventionally used, is proposed as a useful tool for the purpose of diagnosing various dynamic solid-plasma phenomena occurring in bulk semiconductors. First, the dynamic characteristics of the Schottky probe are predicted, based upon the simplest “diode theory”. Consequently, although the results be valid only qualitatively at this stage of the studies, it appears still useful for analyses of various dynamic plasma phenomena. The results of the theoretical prediction are that the probe can detect (1) the time-dependent variation of the space potential in semiconductor at forward bias condition, (2) the variation of the density of minority carriers at reversed bias condition, and (3) the combined effects at the floating operational condition.
The experimental examination for the above-mentioned theoretical prediction has been performed by making use of the phenomenon called “photo-electromagnetic effect.” The results experimentally obtained are qualitatively consistent with those of the theoretical prediction.
On Some Monotonic Approximations for Systems of Non-Linear Heat Propagations
Authors: Kawarada Hideo
Published: November 2005

By the iteration method, some monotonicity and inclusion principles for the coupled nonlinear heat equations are established. Our results will give an insight into an approximating method for the coupled nonlinear heat propagations. At the same time, the above approximating method also shows the existence and uniqueness of the solutions.
Sticking Coefficients and Critical Condensation Conditions of Nickel on Polyfluoroethylene-Propylene
Authors: Murakami Yoshio
Published: November 2005

The sticking coefficient and critical condensation of nickel vapor on PFEP (polyfluoroethylene-propylene) substrates have been studied between the incident beam fluxes of 3×1014 and 2×1016 atoms/cm2·sec and the substrate temperatures of 230 and 280°C. Measurements were made by using a separate substrate for each exposure and keeping both the flux and the temperature constant during a run.
Experimental results are analyzed by using the atomistic model of nucleation theory by Lewis, which suggests an adsorption energy of nickel atoms on PFEP of 0.8 eV and a critical size of one atom. However, if E

a
/E

b
<0.5, pair evaporation becomes more likely than dissociation, and Zinsmeister's theory is plausible. The latter may explain qualitatively the induction periods which have been observed in the sticking coefficient measurements.
Electrical Properties of Rutile (TiO2) Thin Film
Authors: Katsuta Yukio , Akahane Ryozo , Yahagi Kichinosuke
Published: November 2005

Rutile thin films of Au(Ti, Al)–TiO2–Pt sandwich system were prepared on a substrate glass by evaporation of Ti metal and oxidation of it by heat treatment. Through AC and DC measurements, the capacitance obtained was about 2000 pF/mm2, the dielectric constant was estimated as 60∼110, tan
δ was 1∼10%, the conductivity was about 10-13Ω-1cm-1 and the electrical strength was 5∼10 V (0.3∼0.5 MV/cm), respectively. In the micro-sec- and micro-sec-pulse conduction measurement, the relation of current and time became I∝t
-n
, in which the value of n was 0.7∼0.8. The polarity effect on the current was considered to be due to the work functions of electrodes. The current carrier was estimated to be electronic from the measurement of photoconduction and the polarity effect in the pulse conduction.
Geometry of the Crystal Lattice of β-Tin
Authors: Yomogita Kazuo
Published: November 2005

The arrangement of atoms in a β-tin crystal lattice is studied. Interplanar spacings between lattice planes and the minimum atomic distances in glide are calculated. Geometrical approaches are carried out on the stacking of lattice planes and the atomic arrangement of jogs which are produced by intersection of dislocations or emission of vacancies. The results are discussed in connection with the reported slip systems and the observed phenomena in plastic deformation. Elastic interaction between a slip and a forest dislocation is studied, and the force exerted on each part of the slip dislocation and the total force are calculated for every combination of relative locations and Burgers vectors of both dislocations.
On the Growth of Copper Whiskers by Halide Reduction and Their Perfection
Authors: Gotoh Yoshihiko
Published: November 2005

Defect structures of copper whiskers, grown by hydrogen reduction of copper iodide, whose diameter ranges from several hundreds Å to one micron and from 20 to 100 µ, have been examined under 100, 500 and 1000 kV electron microscopes and a fine focus X-ray diffraction microscope, respectively, in order to study their growth process and peculiar mechanical properties. Observational results show that there is no dislocation in a large number of copper whiskers having not only straight shape but also kinked, curved, spiral and irregular-thickness ones. On a few specimens, dislocations with various forms such as straight, jogy, helical, tangled and of loop are observed. In some whiskers, dot-like defects are observed over the whole of them. At tips of the whiskers, the fragment containing impure crystallites and also the lattice defects are often observed, which may be associated with the growth mechanism of their tip growth.