bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermodynamical Analysis of AlGaInP Vapor Growth
Authors: Koukitu Akinori , Seki Hisashi
Published: November 2005

A method of computation developed for the analysis of the equilibrium state of a multi-component system has been applied to the Al–Ga–In–P–Cl–H system. The general features of the equilibrium partial pressures are found to be quite similar to those for indium containing ternary and quaternary alloys. The deposition diagram for Al
x
Ga
y
In1-x-y
P alloy compositions is computed as a function of the input mole ratios. At high temperature, the aluminum component deposits, while at low temperature, the indium and gallium components deposit preferentially. It is predicted that the growth of Al
x
Ga
y
In1-x-y
P is possible at about 700°C.
Effects of Silicon-Nitride Films on the Electronic Properties of Si–SiO2 Interfaces
Authors: Kamada Mikio , Yagi Atsuo
Published: November 2005

The electronic properties of Si–SiO2 interface states in Metal-Nitride-Oxide-Silicon (MNOS) with thick oxide films are investigated. It is shown that a large number of acceptor-like interface states are created when MNOS is annealed at high temperatures, and that subsequent low temperature hydrogen annealing reduces the number of these states. We found that the energy distribution of the interface states is independent of their density. The possible cause of these interface states may be thermal stress induced at the interface.
Injection Locking Effect of Optical Detection by Glow Discharge in DC Magnetic Field
Authors: Ueda Hiroyuki , Miyawaki Sawami , Iida Yukio , Morita Masanobu
Published: November 2005

Optical wave detection by glow discharge in a DC magnetic field (PIG-type) is described. The detection sensitivity becomes a maximum at the magnetic flux density at which the electron cyclotron frequency is almost equal to the electron-neutral molecule collision frequency. In addition, when the microwave signal exists at the same time, the injection locking effect comes into operation, and the noise power decreases. The effect is strongest when the incident microwave power is more than –10 dBm, and its frequency is equal to the electron cyclotron frequency, the frequency of the electron circular motion, or their multiples or fractions.
Extreme Ultraviolet Spectra of Emission from Plasma Focus. II. ArXI to ArXV Ion Lines from 130 to 230 Å
Authors: Hasama Toshifumi , Fukuda Kuniya
Published: November 2005

Extreme ultraviolet emission from multiply-ionized Ar-ions was observed in plasma focus discharges in ambient Ar gas with a ceramic rod set on a Cu anode. The spectrum of the emission was observed in the wavelength range from 60 to 500 Å with a grazing-incidence spectrograph. The spectral lines observed were mainly 2s-electron excitation lines from ArXI(2s22p4) to ArXV(2s2)-ions in the range from 130 to 250 Å. The relative line-intensities were determined, and the lines have been tabulated together with their relative intensities. Four lines from ArXI to XIII-ions have been newly identified, and the energy values of the levels ArXI 2p6
1S0 and ArXIII 2p4
1D2 have been determined. Furthermore, 11 lines from doubly-excited levels of ArXII to XIV-ions have been observed at the wavelengths predicted by Fawcett.
Predictions of Cluster Beam Production with Slit-Throat Nozzle by Classical Condensation Theory
Authors: Be Suck Hee , Yano Katsuki , Kawai Shigeru
Published: November 2005

Classical condensation theory is used to predict cluster production in a nozzle with a slit-throat. The basic idea underlying this nozzle is that a slit-throat nozzle is approximately equivalent to a linear array of axisymmetric nozzles of diameter equal to the throat width. The results of computation show that the slit-throat nozzle can produce a cluster beam of high total flux with a constant cluster size, and are approximately in agreement with those of experiments.
TSC Study on Interfacial Phenomena in PE (Polyethylene)-EVA (Ethylene-Vinylacetate Copolymer) Laminated Films
Authors: Suzuoki Yasuo , Cai Guo-xiong , Mizutani Teruyoshi , Ieda Masayuki
Published: November 2005

Thermally stimulated current (TSC) experiments were carried out on laminated films of PE (polyethylene) and EVA (ethylene-vinylacetate copolymer). When PE-EVA laminate was polarized with a positive voltage on the EVA side (PE-EVA ⊕), a TSC peak (P4) appeared which was not observed in PE, EVA or PE-EVA \ominus. The P4 peak intensity shows non-linear poling field dependence, with a maximum around 107 V/m. TSC results on three-layer PE-EVA-PE and EVA-PE-EVA films, together with the above results, led to the following conclusions: (i) carrier traps exist at the PE-EVA interface (depth: ca. 1.5 eV) (ii) these traps and positive carriers injected from the anode into the EVA (or generated near the anode-EVA interface) are responsible for the P4 peak.
New Logic Circuit with DC Parametric Excitation
Authors: Sugahara Masanori , Kaneda Hisayoshi
Published: November 2005

It is shown that dc parametric excitation is possible in a circuit named JUDO, which is composed of two resistively-connected Josephson junctions. Simulation study proves that the circuit has large gain and properties suitable for the construction of small, high-speed logic circuits.
Changes in Yield Stress of NaCl: Pb2+ Crystals during Dissolution and Precipitation of Solid Solutions
Authors: M. E. Orozco , A. A. Mendoza , Soullard J. , O. J. Rubio
Published: November 2005

A study of the changes in the hardening of lead-doped NaCl under dissolution and precipitation of solid solutions is reported. Optical absorption measurements were performed in parallel with mechanical ones in order to obtain additional information on the change in state of the impurity ions in the samples. Values for the yield stress corresponding to coherent and incoherent precipitates of lead ions in NaCl have been determined. It is found that the increase in the hardening of freshly-quenched samples is proportional to C
2/3 in the range of lead concentration 30→1200 ppm.
Electrical Properties of Ti–Fe Films
Authors: Kurita Noriaki , Igasaki Yasuhiro , Mitsuhashi Hiroji
Published: November 2005

Ti
x
Fe1-x
(0<x<1) films were prepared by composite-cathode sputtering and their electrical resistivity (ρ) was measured. The plot of ρ against x was bell- shaped, with two noticeable dips at 0.33 and 0.47 corresponding to the intermetallic compounds of TiFe2 and TiFe, respectively. Films of the amorphous phase with x=0.7 had a maximum ρ of about 700 µΩ-cm and a TCR of -200 ppm/K. ρ appears to reflect the structural features of the films.
Evaluation of the Wiener Spectrum of Radiographic Screen-Film Systems by Entropy
Authors: Uchida Suguru , Hatagawa Masakatsu , Abe Hiromu , Fujita Hiroshi
Published: November 2005

The Wiener spectra of radiographic screen-film systems are assessed by the entropy method, which is considered to be a method of evaluation based on the precision of measurements. The spectral resolution associated with the fluctuation and gradient of the measured spectra can be calculated by this method. The relative spectral resolution of the Wiener spectrum is defined by the relative efficiency of transmission. Using the results of entropy calculations, the Wiener spectra of three screen-film systems are evaluated by comparing the values of the transmitted information or the relative spectral resolution of each system. It is concluded that a screen-film system should be evaluated by both the Wiener spectrum, related to the accuracy, and the entropy, related to the precision.
Characteristics of the JAERI Circular Magnetic Multipole Line-Cusp Ion Source
Authors: Sakuraba Junji , Akiba Masato , Arakawa Yoshihiro , Kawai Mikito , Tanaka Shigeru
Published: November 2005

A circular magnetic multipole line-cusp ion source has been developed for use as a short-pulse neutral beam injector. This source has produced hydrogen ion beams of up to 30 A at 30 keV for 100 ms. The ion saturation current density was uniform within 55% over the 18.5 cm diam. area of the extraction grid. The arc efficiency for a beam current of 30 A was 1.2 A/kW with an arc current and voltage of 260 A and 100 V, respectively, and the pressure in the source was 3.5 mTorr. The ion species ratio from the source was measured and proton ratios exceeding 70% were obtained at an ion current density of 0.23 A/cm2.
Structure of Ti–Fe Alloy Films Prepared by Composite-Cathode Sputtering
Authors: Kurita Noriaki , Igasaki Yasuhiro , Nakamura Yasuo , Shimaoka Goro , Mitsuhashi Hiroji
Published: November 2005

Films of the binary alloy Ti
x
Fe1-x
(0<x<1) of uniform composition, from 500 Å to 1 µm thick, were prepared by d.c. sputtering with a composite cathode containing a Ti plate and Fe wires, or an Fe plate and Ti wires. Analyses of the films by EPMA and Auger electron spectroscopy showed that the composition was uniform over an area of about 20×20 mm2. X-ray and electron diffraction analyses of the the films showed the existence of amorphous phases at 0.05<x<0.30, 0.35<x<0.50 and 0.55<x<0.83 and a β-Ti (b.c.c.) phase at 0.80<x<0.94, in addition to an α-Fe (b.c.c.) phase at 0<x<0.30, a TiFe2 (hexagonal) Laves phase at 0.25<x<0.35, a TiFe (CsCl type) phase at 0.45<x<0.55 and an α-Ti (h.c.p.) phase at 0.83<x<1.
Impurity Evolution in a Beam-Heated Tokamak
Authors: Kishimoto Hiroshi , Tani Keiji , Nakamura Hiroo
Published: November 2005

Impurity evolution during neutral beam injection has been investigated in a large tokamak with the first wall made of low-Z (carbon), medium-Z (titanium) and high-Z (molybdenum), based on a simple model of wall-released impurity behavior. The use of low-Z material seems helpful in reducing impurity contamination in a high-temperature plasma with material limiters. A divertor is effective for controlling of wall-sputtered impurities for any of the wall materials.
Geometrical Injection Efficiency of a Neutral Beam Having a Circular Cross Section
Authors: Maekawa Akiji , Sato Tadashi , Uede Taisei
Published: November 2005

A normalized equation that gives the geometrical injection efficiency E in a neutral beam injector (NBI) having a circular cross-sectional beam is shown. The efficiency E is defined as the ratio of the fast neutral beam intensity into the exit port of the NBI to the total beam intensity which arrives near the port. The solution of the equation is represented as a special diagram which is available for the design of a NBI.
Analyzed results are as follows: (1) The efficiency E is a function of five parameters: a, beam radius on the extraction electrode; l, target distance; f, beam focal length; w, divergent angle of a beam element; and b, exit port radius. And E can be represented by a normalized equation using two normalized parameters. (2) The efficiency E is a maximum when the focus point of the ion source is in the port.
Thermally-Stimulated Currents in Polytetrafluoroethylene in the Neighborhood of Room-Temperature Transitions
Authors: Ikeda Susumu , Matsuda Kazuo
Published: November 2005

Thermally stimulated currents (TSC) in polytetrafluoroethylene in the neighborhood of room-temperature transitions were measured. Information on the TSC peaks arising from room-temperature transitions can be summarized as follows. The depolarization current did not contribute to the TSC peaks arising from room-temperature transitions. TSC peaks due to the temperature variation of the dielectric constant arising from room-temperature transitions were found under a bias electric field, and the temperature dependence of the dielectric constant was evaluated from the TSC. A pyroelectric current peak which was reversible for the temperature variation arising from the room-temperature transition was found.
Temperature Dependence of Photoconduction in Polyethylene Induced by Vacuum-Ultraviolet Light
Authors: Kitani Isamu , Nojima Ken-ichi , Yoshino Katsumi , Inuishi Yoshio , Kawatsu Motoo
Published: November 2005

Intrinsic photoconduction in polyethylene (PE) and its dependence on temperature have been investigated in the photon energy range between 7 eV and 11.5 eV. The band gap of PE is evaluated from the photoconduction spectra. The rise time of the photocurrent increases exponentially with the reciprocal of the temperature, corresponding to a decrease in the carrier mobilities at lower temperatures. In low-density PE, the steady photocurrent increases greatly with temperature in the room-temperature region but saturates at 40°–50°C, tending to decrease slightly at higher temperatures, regardless of the applied field and the light intensity. Photoconduction in high-density PE has very different features compared with that in low-density PE. The temperature and crystallinity dependences seem to suggest the migration of ionic spieces in low-density PE.
AC Temperature Calorimetry for Thin Films at Low Temperatures
Authors: Suzuki Takao , Tsuboi Takefumi , Takaki Hideo
Published: November 2005

An apparatus for heat-capacity measurements of thin films is devised for the temperature range 0.4–3.5 K using ac temperature calorimetry. The total heat capacity of the addenda is about 2×10-9 J/K at 0.5 K and a heat-capacity change as small as ∼5×10-12 J/K is detectable at this temperature. The performance of the apparatus is checked by measuring the superconducting transition of a thin Al film having a thickness of 2040 Å.
Dual Display System for Multidimensional Data Analysis of High-Energy Physics
Authors: Hattori Yukiya , Hamatsu Ryosuke , Hirose Tachishige , Kitamura Shoichi , Yamagata Taketora
Published: November 2005

We have constructed an interactive graphic system with two cathode ray tube displays which we have called the Dual Display System (DDS) for quick and efficient data analysis in high energy physics. We used the new system to analyze data from 6 GeV/c π-p inelastic reactions and found that the system could separate the reaction channels more cleanly than conventional methods and thus provide reliable information on the reaction mechanisms. This paper describes the new system and presents the software techniques for multidimensional analysis used with it.
Unsteady Flow of Suspension through a Pipe
Authors: Srivastava L. M. , Agarwal R. P. , Srivastava V. P.
Published: November 2005

The unsteady flow of a binary mixture of fluids in a long rigid cylinder of circular and sectorial cross-sections, under the influence of an arbitrary time varying pressure gradient, is studied. Velocity of both the phases are explicitly determined for various particular pressure gradients of physical importance. Finally, to gain insight into the patterns of flow, numerical study of the results has been made using a digital computer. A strong motivation of the present analysis has been the hope that such a theory of fluids is useful in providing some insight in rheological properties of complex fluids as polymers, liquid crystals and, in particular, blood in the vessels of small diameter. Also the theory of mixture of fluids might provide an improved understanding of such diverse subjects as diffusion of proteins, swimming of microorganism and particle diposition in respiratory tract.
Ellipsometric Measurement of Damage Depth Profiles for Ion Beam Processed Si Surface Layer
Authors: Ohira Fumikazu , Itakura Masayuki
Published: November 2005

The damage depth profiles in ion-implanted or rf sputter-etched Si surface layers have been measured by combining ellipsometric measurement with step removal. The ellipsometric measurements were compared with those of Auger Electron Spectroscopy for the ion-implanted surfaces, and with oxidation Sirtl etching check measurements (OS check) for the rf sputter-etched surfaces. It was found that a damage peak position exists inside the surface layer, e.g. at a depth of about 700 Å for 70 keV phosphorus ion implantation in Si. This position exists at the surface side rather than at the dopant peak position. The change in the refractive index is caused primarily by the change from single crystal to the amorphous (damage) state. It is also verified that the damage region measured ellipsometrically corresponds to the distribution of oxidation-induced stacking faults (OSF) for rf sputter-etched specimens.
Photo-Induced Stress Relaxation in Amorphous Selenium Films
Authors: Koseki Hideo , Odajima Akira
Published: November 2005

Photo-induced stress relaxation was measured in amorphous selenium (a-Se) films with an a-Se/mica bimetallic structure. Thermally-induced stresses in these a-Se films were rapidly relaxed by illumination at temperatures from -50°C to room temperature. The photo-induced stress relaxation was approximated by an exponential decay at various levels of light intensity, and the activation energy of the photo-induced stress relaxation is estimated to be of the order of 0.1 eV. This can be explained in terms of the structural relaxation in local atomic rearrangements caused by illumination.
Numerical Solutions of Basic Equations for Kick-Out Mechanism of Diffusion
Authors: Kitagawa Hajime , Hashimoto Kimio , Yoshida Masayuki
Published: November 2005

The basic equations for the kick-out mechanism of diffusion are a set of non-linear differential equations. These equations are solved numerically for the diffusion of gold in silicon at 1100°C for both in-diffusion and annealing, and analytical expressions for the solutions are given.
It is found that the numerical solution for the interstitial gold atoms reaches the thermal equilibrium value most rapidly. The time at which the interstitial gold atoms reach their thermal equilibrium, and the time at which the interchange reactions between substitutional and interstitial gold atoms reach a local equilibrium are obtained from the analytical expressions of the numerical solutions.
The NMR Study of Li Ion Motion in K3LiNb6O17 and K3LiTa6O17
Authors: Tanaka Junzo , Onoda Yoshito , Tsukioka Masayuki , Shimazu Masaji , Ehara Shaw
Published: November 2005

The temperature dependences of the NMR relaxation times of 7Li in K3 LiNb6O17 (KLN–2) and K3LiTa6O17 (KLT–2) are reported. The logarithms of the relaxation times give straight lines against the inverse temperature, and the activation energies are estimated to be 0.29 eV and 0.33 eV from the longitudinal relaxation times for KLN–2 and KLT–2, respectively. The motion of Li ions observed by NMR is discussed in connection with the ionic conduction in these materials and it is shown that the relaxation process is due to short-range ionic motion.
Application of Time Domain Reflectometry Covering a Wide Frequency Range to the Dielectric Study of Polymer Solutions
Authors: Nakamura Haruki , Mashimo Satoru , Wada Akiyoshi
Published: November 2005

Time domain reflectometry is applied to obtain dielectric relaxation spectra of polymer solutions covering a wide frequency range from 100 kHz to several GHz. The measuring system of the difference method is precisely described, including cell design, data acquisition system and calculation to obtain the complex permittivity. The performance of the system is demonstrated by measurements of several polymer solutions in both polar and nonpolar solvents.
Electrical Breakdown of Plasma-Polymerized Styrene Thin Films
Authors: Hikita Masayuki , Matsuda Akinori , Nagao Masayuki , Sawa Goro , Ieda Masayuki
Published: November 2005

The electrical breakdown of plasma-polymerized styrene thin film (PPS) was studied by taking advantage of self-healing. The electric strength F
B was almost independent of temperature from -196 to 200°C, and strongly depended on the rate of voltage increase even at a slow rate of increase. The breakdown characteristics were influenced by the electrode metal and the ambient atmosphere, but not by X-ray irradiation or photoillumination. The experimental results are used to discuss the breakdown mechanism of PPS through existing breakdown theories. As a result, no single breakdown process was considered as a possible breakdown mechanism, and we thus obtained important conditions for presenting a new breakdown model; the breakdown of PPS will be determined by a thermal criterion, and it will be closely related to a temperature-independent injection process.
Performances of Josephson Junction Harmonic Mixers with Harmonic Numbers 1–8 at 70 GHz
Authors: Kita Sadamu , Fujisawa Kazuo
Published: November 2005

We have carried out a series of experiments at 70.03 GHz on Josephson junction harmonic mixers with harmonic numbers 1–8, using an identical Josephson junction. It was found that Josephson junction harmonic mixers operate differently depending on whether their harmonic numbers are odd or even. With odd-harmonic mixers, only finite-bias operation is possible, while with even-harmonic mixers, finite-bias and zero-bias operations are both possible. It is noted that a 2nd-harmonic mixer has a conversion efficiency equal to or higher than that of a fundamental mixer. The dependence of the conversion efficiency (η) on the harmonic number (N) was also studied, and the following approximate relations were determined: η∼N
-1.6 for finite-bias operation and η∼N
-1.4 for zero-bias operation.
Theoretical Study on Optical-Pumping Self-Focusing
Authors: Yabuzaki Tsutomu , Hori Hirokazu , Kitano Masao
Published: November 2005

A theoretical study is made on the steady-state self-focusing and self-defocusing of a circularly-polarized laser beam, occurring in an atomic vapor mixed with a buffer gas at a relatively high pressure. The presence of the buffer gas removes the theoretical difficulties arising from hole-burning, the transit time, and hyperfine pumping. It also localizes the optically-pumped atoms in the vicinity of the laser beam, so that self-focusing occurs even at extremely weak light intensities. A preliminary experiment is also descirbed, the results of which show that optical-pumping self-focusing can be observed at laser intensities down to 30 µW.
Hydrogen Ion Species Analysis and Related Neutral Beam Injection Power Assessment in the Heliotron E Neutral Beam Injection System
Authors: Sano Fumimichi , Obiki Tokuhiro , Sasaki Akihiko , Iiyoshi Atsuo , Uo Koji
Published: November 2005

The hydrogen ion species in a Heliotron E neutral beam injection system of maximum electric power 6.3 MW were analyzed in order to assess the neutral beam power injected into the torus. The maximum proton ratio of the cylindrical bucket type ion source used was observed to be more than 90 percent assuming that the angular divergences for the respective species in the beam are the same. The experimental data are compared with calculations using a particle balance model. The analysis indicates that the net injection power reaches nearly 2.7 MW at the optimal conditions of the system considering the geometrical limitation of the neutral beam path.
Etching of SiO2 Films by Si in Ultra-High Vacuum
Authors: Tabe Michiharu
Published: November 2005

SiO2 etching resulting from reaction with impinging Si or substrate Si was clearly observed in an ultra-high vacuum by using step measurement, Auger electron spectroscopy and/or ellipsometry. In etching by impinging Si, the etching rate decreases with the substrate temperature, and increases with the Si impinging rate. These results are explained by a model proposed here that involves Si adsorption on SiO2, and a subsequent chemical reaction. It was found that SiO2 films thinner than 2.5 nm are etched by the same reaction with substrate Si, whereas those thicker than 2.5 nm are not etched at all, since reaction products cannot diffuse through the SiO2 film to the vacuum.
These phenomena can be used in Si molecular beam epitaxy.
Frequency of Sound from Singing Sand
Authors: Nishiyama Kyoshin , Mori Senji
Published: November 2005

The singing sand from Kotobikihama, when placed in a container, emits a musical sound on being struck with a rod. The frequencies of the sound have been studied under various conditions of rod and container. The results of our experiment can be accounted for by the “spring model” in which the rod, the container and part of the sand constitute a vibrating system with the sand playing the role of a spring. The spring constant is estimated as about 4.8×108 dyn/cm. Another way to estimate the spring constant is from the relation between the pressure and the displacement of the rod when the rod is pushed into the sand slowly. The agreement between these two spring constants is fairly good.
A Highly-Sensitive AC Interferometric Dilatometer
Authors: Uchino Kenji , Nishida Shoji , Nomura Shoichiro
Published: November 2005

An interferometric-type dilatometer has been constructed which is capable of resolving AC linear displacements of 10-13 meter (0.001 Å) and can be used for the direct measurement of piezoelectric and electrostrictive deformations. Using DC servo stabilization of the optical pathlength, the mode of sensing the light intensity change generated by the alternating crystal deformation has been improved remarkably. Some experimental data are given on piezoelectric and electrostrictive crystals and ceramics.
Examination of the Properties of Superconducting Nb–Ge Films Prepared by DC Magnetron Sputtering
Authors: Kubo Shugo , Nakamura Kiko , Igarashi Masaru
Published: November 2005

The superconductivity and film structure of A15 Nb–Ge were extensively examined through film preparation utilizing the characteristic features of dc magnetron sputtering. T
co 22.9 K and Δ
T
c 0.5 K films of 2400 Å thickness were obtained. Films of T
co>22 K and Δ
T
c<1 K could be prepared with good reproducibility. As a result of Auger analysis, it was concluded that impurities, especially oxygen, were unnecessary for metastable high-T
c Nb3Ge phase growth. Impurity oxygen was concentrated into a depositing film from surface impurity-rich layer and tended to make a hexagonal Nb5Ge3 phase formed. In order to control this and to attain high-T
c, film fabrication with a high deposition rate over short sputtering time was effective. A high-T
c Nb3Ge phase grew on a base layer 1000–1500 Å thick. The layer was found to contain no impurities and rather to be rich in anti-site defects.
Improvement in Trade-Off between Turn-Off Time and Other Electrical Characteristics of Fast-Switching Thyristors
Authors: Tada Akiharu , Nakagawa Tsutomu , Hagino Hiroyasu
Published: November 2005

Trade-offs between turn-off time, on-state voltage and reverse blocking voltage should be improved in producing fast-switching thyristors with higher blocking voltage and current handling capabilities.
It is well known that the electrical characteristics of a thyristor depend strongly on the gold distribution in its nB layer.
The influence of a boron-diffused layer on the gold distribution in a silicon wafer has been investigated. It has been found that the gold distribution gradient in the central region of the wafer is varied by the existence of a highly-concentrated layer of boron on one side of the wafer, and that if this phenomenon is applied to the production of thyristors, the trade-offs between turn-off time, on-state voltage and reverse blocking voltage are greatly improved.
Further, the effect of the gold distribution gradient on the turn-off time, on-state voltage and reverse leakage current is discussed theoretically.
Gas Mixing Effect on Ion Current Spectrum and Its Application to Optimize Implantation Source Gas Composition
Authors: Irita Yukio , Kajiyama Kenji
Published: November 2005

In a Penning discharge ion source, He (small atomic number) and Ar (large atomic number) gases are shown to play the roles of diluent and excimer, respectively, when mixed with O2. The gas composition is optimized at Ar(0.1%)–He(90%)–O2(10%), producing a high O+ ion current as well as good operation and maintenance of the implanter. In both N2–O2 gas mixture and N
x
O
y
compound gas, the O+ ion current is almost proportional to the oxygen content. A high NO+ molecular current is obtained with NO compound gas, rather than with N2(50%)–O2(50%) gas mixture. The present results are a valuable guide to the selection of other gas mixtures for implantation.
Thermal Neutron Cross-Sections of 23Na and 41K
Authors: Kaminishi Kunio , Shuin Takashi
Published: November 2005

The cross-sections of the 23Na(n, γ)24Na and 41K(n, γ)42K reactions at the thermal energy are determined using the activation method. The beta activity of powdery samples is measured, and consideration of the backscattering due to the bottom of the vessel is important. This paper introduces a new method for determining this factor. For the 23Na(n, γ)24Na and 41K(n, γ)42K reactions, the cross-sections obtained by this method are 577±8 mb and 1.57±0.17 b respectively.
Stress Relaxation Study of Fine Structure of α-Loss Band of Branched Polyethylene
Authors: Yamada Yoshinori , Kakizaki Maeko , Hideshima Teruo
Published: November 2005

In order to clarify the effect of branching on the α-loss band in polyethylene, the shear relaxation modulus of samples with various degrees of branching is measured from 5 sec to 900 sec, between -90°C and 60°C. Two relaxations named α1 and α2 in order of ascending temperature are observed separately and reduced to master curves by the method of reduced variables. The activation energies for the α1- and α2-relaxations are ca. 26 kcal/mol, and 46 kcal/mol respectively. The activation energies and the shapes of the relaxation spectra for these relaxations are independent of the crystallinity and degree of branching. As the degree of branching increases, the relaxation strength for the α1-relaxation increases and that for the α2-relaxation decreases, while both relaxations shift to lower temperatures. These results are compared with the existing molecular theories.
Formation of α Form Nylon 12 under High Pressure
Authors: Hiramatsu Nobuyasu , Hashida Shigesou , Hirakawa Susumu
Published: November 2005

The formation conditions of α form Nylon 12 under high pressure from the melt and from the quenched state were investigated by means of high-pressure differential thermal analysis and wide-angle X-ray diffraction. The α form was formed by crystallization from the melt above 200 MPa, and the γ form disappeared in the sample obtained above 500 MPa. The quenched state was transformed into the α form at lower temperature than the melting point of the α form under high pressure, whereas the γ form was hardly transformed at all. The thermal behavior of the α form at atmospheric pressure was also studied. Two endotherms due to the meltings of the α and γ forms and one exotherm due to the α to γ form transformation were observed. This transformation occurred without melting of the α form at a slow heating rate and was regarded as a monotropic transition.
Reactive Ion Beam Etching of SiO2 and Poly-Si Employing C2F6, SiF4 and BF3 Gases
Authors: Okano Haruo , Horiike Yasuhiro
Published: November 2005

A magnetron ion gun, improved by using a permanent magnet to produce a larger magnetic flux density at the annular gap, has been applied to reactive ion beam etching. A discharge mode, in which the ion accelerating voltage remains at a constant low value even when the input power is increased, was found. In the constant-voltage mode, the SiO2 to poly-Si etch rate ratio for C2F6 gas increases with increasing discharge current, while the ratios for SiF4 and BF3 are almost unity. Also, the effect of adding O2 or H2 gas was investigated. The addition of H2 to the outside of the ion gun gives a selective ratio of SiO2 to poly-Si as high as 25.
Analysis of Pyroelectricity of Poly(vinylidene fluoride) by Residual Charge Measuring Technique
Authors: Inoue Nobukazu , Takada Tatsuo , Sakai Takao , Nakamura Ken'ichi
Published: November 2005

The machnism of the pyroelectricity of poled β-PVDF was studied, introducing a newly-developed method of measuring the residual charge density on the electrodes sandwiching the poled film. Homocharge or heterocharge in the dielectric can be easily distinguished and quantified by the new technique. The dependence of the poling parameters (electric field, temperature, time) on the residual charge density was investigated in detail, and poled β-PVDF proved to be a strong heterocharge-electret. The heterocharge is probably due to dipole orientation in the β-form crystalline region. The mechanism of the pyroelectricity is attributed to thermal reversibility of the density of heterocharge generated by poling from a comparison of the effect of the sample temperature on the residual charge density and the pyroelectric effect on the Thermally-Stimulated-Current.
New Laser Emission from NH3 Optically-Pumped by TE–CO2 Laser
Authors: Nishi Yoshio , Horiuchi Yasuo , Wada Satoshi , Sokabe Noburu , Murai Akira
Published: November 2005

Nineteen new laser lines have been found from NH3 pumped by a TE–CO2 laser. These lines span the wavelength range from 20.9 to 148.7 µm. Assignments are made on 17 lines and three of them are ascribed to stimulated Raman scattering. Two lines are left unassigned.
Long-Lived (GaAl)As DH Lasers Bonded with In Produced by Eliminating Deterioration of In Solder
Authors: Hayakawa Toshiro , Yamamoto Saburo , Matsui Sadayoshi , Sakurai Takeshi , Hijikata Toshiki
Published: November 2005

Long-lived (GaAl)As DH lasers bonded with In solder have been produced using Mo as a barrier metal. The amount of Au on the Mo was reduced to much less than the amount of In solder to eliminate the deterioration of the latter. The intermetallic formation between In and Au was investigated using a simulation method. An accelerated reliability test at 50 and 70°C, gave the activation energy of degradation as 0.52 eV. The mean time required for a 50 mA driving current increase in these long-lived devices was estimated to be 1.9×106 hours at 25°C in operation at 5 mW/facet.
Surface Silicon Crystallinity and Anomalous Composition Profiles of Buried SiO2 and Si3N4 Layers Fabricated by Oxygen and Nitrogen Implantation in Silicon
Authors: Maeyama Satoshi , Kajiyama Kenji
Published: November 2005

Buried SiO2 and Si3N4 with residual crystalline surface silicon were fabricated by implantation of O+, O2
+, N+ and N2
+ into single-crystal silicon with 0.6–3.0×1018 atom/cm2 dose at an energy of 70–150 keV/atom. The implanted silicon wafers were annealed at 1150°C to recover the surface silicon crystallinity and to ensure good Si–O and Si–N bonds. After this, high-quality crystalline silicon layers were grown epitaxially on the implanted surface. The surface silicon damage and the buried layer composition profiles were measured reliably by the Rutherford backscattering method together with the channeling technique. In the buried layers, the O/Si ratio did not exceed the stoichiometric ratio of 2.0 for SiO2 even before annealing. However, the N/Si ratio exceeded the stoichiometric ratio of 4/3 for Si3N4.
Electrical and Structural Properties of Ion-Implanted and Post-Annealed Silicide Films
Authors: Sorimachi Yoshio , Ishiwara Hiroshi , Yamamoto Hiroshi , Furukawa Seijiro
Published: November 2005

The changes in the electrical and structural properties of metal-silicide films caused by ion implantation and subsequent thermal annealing have been investigated. Epitaxial silicide films such as those of CoSi2, NiSi2 and Pd2 Si grown on Si (111) substrates were implanted with Ar ions and annealed in a vacuum furnace at temperatures ranging from 200 to 800°C. Rutherford backscattering and channeling techniques and the four-point probe method were used to measure the crystalline quality and the sheet resistance of the films, respectively. It was found that the sheet resistances of CoSi2, NiSi2 and Pd2Si films were increased by factors of 70, 6, and 3, respectively, by implantation to a dose of 1×1016 Ar-ions/cm2, but that they were almost restored by subsequent annealing to the values before implantation. A phase transformation from Pd2Si to PdSi was also observed in the high-temperature annealing of the implanted Pd2Si films.
Cracks and Corrosion in PSG Passivation Glass
Authors: Takahashi Kenji , Kitajima Kazuya , Imaoka Sumio
Published: November 2005

Aluminium corrosion and cracks in single-layer and triple-layer phosphosilicate glasses (PSG) were studied. The optimum phosphorus concentration for producing PSG passivation glass was found to be 3 to 5 mol%. The corrosion of the aluminium was found to proceed by two different processes; a simple electrolytic reaction with water induced by high current density and a cathodic reaction due to the high phosphorus concentration. In the formation of cracks in the glass, the deposition temperature was very important, as was the phosphorus concentration.
Electron Beam Vacuum Lithography Using a Plasma Co-Polymerized MMA–TMT Resist
Authors: Yamada Masao , Tamano Junji , Yoneda Katsumi , Morita Shinzo , Hattori Shuzo
Published: November 2005

The dry development of an Sn containing electron-beam-sensitive resist produced by plasma polymerization is described. The dry development was performed using self-development, with good results. In order to raise the e-beam sensitivity for self development, a little metal was added to an organic resist. It was found that a plasma co-polymerized methyl methacrylate tetramethyltin resist “PP (MMA–TMT)” had a sensitivity of 20 µC/cm2 and a γ value of 3.
Antimony Particles with {200} Twinning Prepared by Vacuum Evaporation
Authors: Yamamoto Yoichi , Tanaka Yoshiaki , Suganuma Ryozi
Published: November 2005

The external shape of antimony particles prepared by vacuum evaporation has been studied by transmission electron microscopy. Particles grown on heated amorphous carbon substrates (200–250°C) in high vacuum have the quadrangular pyramidal shape with sizes from 50 nm to 3 µm. These particles are twinned particles consisting of four thin, wedge-shaped (111) plates twinned on the {200} planes with each other. The atomic movements for the formation of the {200} twinning are also proposed. The bending of each plate due to the formation of a twinned particleis analyzed using bend contours. (Indices are referred to the face-centred rhombohedral cell of axial angle 87°24'.)
Influence of Bonding Wire on Electron Beam in Camera Tube with NEA Cold Cathode
Authors: Hatanaka Yoshinori , Honda Kazuhiko , Ando Takao
Published: November 2005

When an NEA cathode is used in a camera tube, a disturbance of the electric field adjacent to the cathode, produced by the bonding wire needed to apply the bias voltage to the electron emitting layer, causes asymmetric aberrations and distortions in the electron beam spot focussed on the target. We have investigated the influence of the bonding wire on the focusing of the electron beam by computer simulation and have confirmed the results using an experimental camera tube. It was shown that a bonding wire positioned 0.2 mm from the center of the cathode caused aberration in the beam spot and gradual saturation of the landing curve; but when the wire was 1 mm from the cathode center, it had no influence on the beam spot and the landing curve.
Superconducting Tc's of Sputter-Deposited Nb–Ge Films and Tc Nonuniformity within Films
Authors: Suzuki Mitsumasa , Suzuki Nobuaki , Anayama Takeshi
Published: November 2005

The superconducting transition temperature T
c and nonuniformity of Nb–Ge films prepared on sapphire substraies from compound targets by dc sputtering have been studied. The relationships between the transition temperature, the electrical resistivity ratio and the film thickness have been studied using targets with different compositions, and the conditions for preparing high-T
c. Nb–Ge films below ∼2000 Å in thickness have been determined. The T
c values for Nb–Ge films are appreciably improved in films thinner than ∼1000 Å with a Ge-richer target (Nb/Ge=2.8) and onset T
c's greater than 20 K are obtained in films with thicknesses of ∼500 Å. The nonuniformity of T
c in the films has been measured. The high T
c arises from the film surface layer and the T
c variation along the film thickness is greatly affected by changes in the substrate temperature during deposition.
Nb–Te–Nb Josephson mm-Wave Mixer Characteristics and Analysis
Authors: Takayanagi Hideaki , Nagata Koichi , Uehara Shingo
Published: November 2005

An mm-wave mixing integrated circuit with a Josephson junction has been fabricated. An Nb–Te–Nb sandwich-type Josephson junction with no hysteresis on its I-V curve was used as the active element. Both RF and IF circuits were constructed in the form of superconducting microstriplines using an Si wafer as the dielectric layer. The circuit was tested at a signal frequency of 50 GHz, and the conversion efficiency η was measured at -7.44 dB, for a junction with a 0.42 mV I
C
R
N product. The measured efficiency showed good ageement with the theoretical one calculated using the RSJ model and taking the impedance of the RF source into account.
Photoluminescence of Hydrogenated Amorphous Carbon Films
Authors: Watanabe Ichiro , Hasegawa Seiichi , Kurata Yoshihiro
Published: November 2005

Hydrogenated amorphous carbon films have been prepared by the glow-discharge decomposition of ethylene gas. The film shows wide properties depending on gas temperature during discharge. With increasing gas temperature from 200 to 350°C, hydrogen content in the film decreases, and thereby the optical gap decreases from 2.6 to 1.2 eV and the ESR spin density increases from ∼1017 to ∼1019 cm-3. The photoluminescence spectrum consists of two emission bands. The peak energy of the main band shifts from 1.93 to 1.64 eV as the gas temperature increases. Emission intensity is very insensitive to measurement temperature.
Thermal Analysis and Experimental Evaluation of Melting Threshold Energy of Si Thin Film Structure in Laser Annealing
Authors: Murakami Koichi , Takahashi Tetsuo , Koyanagi Tadamasa , Hoh Koichiro , Komiya Yoshio , Tarui Yasuo
Published: November 2005

Simultaneous heat-diffusion equations including laser light absorption in an Si thin film structure are solved analytically to give the time evolution of temperature. In this model, it can be concluded that the threshold pulse energy needed to melt the surface of amorphous Si film depends on the pulse duration, the absorption coefficient, the thickness of the Si film, and the thermal properties of the substrates. Experiments were performed on amorphous Si films of various thicknesses on fused quartz and crystalline Si substrates to verify the analytical results. The samples were irradiated with a Q-switched Nd-YAG laser with time durations of 80 ns at λ=1.06 µm and 50 ns at λ=0.53 µm. The experimental results on the dependence of the melting threshold energy on the thickness of the amorphous Si are in good agreement with the calculated results.
Method for Measuring Rate of Movement of Sand Using Laser Beam
Authors: Yoshida Mizuki , Nakashima Yuhki , Sue Katsumi , Tomita Giiti
Published: November 2005

A new method for measuring the rate of movement of sand using an He–Ne laser beam has been developed. This method enables us to measure the velocity of blown sand in the field. The apparatus is composed of an He–Ne laser, a photo-detection system (slit width; 0.3–3.0 mm), a 5-channel pulse width analyzer and a multi-purpose counter.
When a sand grain passes across the laser beam, a shadow is thrown upon the light-sensitive surface of the photodetector. The change in photocurrent, after amplification and pulse shaping, is fed to the pulse width analyzer. The pulse width includes information on both the velocity and size of the blown sand grains. Using a nearly uniform size of sand grains, the velocity distribution of blown sand can be measured.
Chemical Vapor Transport of ZnTe by the Closed-Tube Method and Its Thermodynamic Analysis
Authors: Nishio Mitsuhiro , Ogawa Hiroshi
Published: November 2005

The transport and growth rates in the ZnTe–I2 system by the closed-tube method are experimentally investigated as a function of the charged iodine concentration in the range ∼2×10-3 mg/cm3 to ∼2×10 -1 mg/cm3. The thermodynamic calculations are described here in detail so as to clarify the transport mechanism in this system. The two reactions, i.e. the dissociative sublimation and the complicated disproportionations corresponding to low and high iodine concentrations respectively, play an important role in the transport process of ZnTe. The experimentally-determined transport rate can be described quantitatively over the whole range of iodine concentration by using the two different values, ∼0.038 cm2/s and ∼0.015 cm2/s, as the mean diffusion constant in the low and high regions of iodine concentration respectively.
A Pulsed Neutral Particle Source for Active Plasma Diagnosties
Authors: Ito Yoshifumi , Nishida Hiroshi , Goto Seiichi , Ishimura Tsutomu
Published: November 2005

A z-pinch gun with a gas puffer was studied as a pulsed neutral particle source for active plasma diagnostics. Typical thermal and drift energies of the gun plasma were 120 eV and 140 eV, respectively. The peak density of fast neutral particles converted from the gun plasma was 6.2×1011cm-3 with an energy of 400 eV at a distance of 1.8 m from the gun. The pulse width was about 4 µsec. It is suggested that this kind of particle source with these values can be used for measuring the spatially-resolved ion temperature of plasmas. The experimental results are analyzed by a collisionless free-expansion model.
Electrical Conduction in Undehydrated Liquid Hydrocarbons in Low Electric Field
Authors: Yatsuzuka Kyoko , Watanabe Akira
Published: November 2005

Electrical conduction in liquid hydrocarbons dissolved in a small amount of water has been observed using three types of electrodes under fairly low electric stresses of 100 to 1000 V. The electrical conduction is attributed to dissociated water molecules and the dependence of the permittivity of host liquid on the conduction is discussed. The observed voltage-current characteristics were found to be expressed as V=k
I

n
(n=0 to 2), while the current is strongly affected by electrically-induced convection.
New Counter-Electrodes Made of Iron Compound-Graphite Mixtures for WO3/Liquid Electrolyte Electrochromic Devices
Authors: Yamanaka Kazusuke
Published: November 2005

New counter-electrodes for WO3/liquid electrolyte electrochromic devices were investigated for the purpose of stabilizing the counter-electrode potential. The potential of counter-electrodes made of an Fe2(WO4)3-graphite or FeK[Fe(CN)6]-graphite mixture is stable enough to drive the cells at a constant voltage. The values or the relative reversible electrode potential for the counter-electrodes with Fe2(WO4)3 and FeK[FC(CN)6] are +400 mV, and +200 mV, with respect to an Ag/AgCl reference electrode, respectively. This potential difference affects the coloration-bleach characteristics of the cells. When the cell is erased at a certain applied voltage, the erasing rate or a cell with the Fe2(WO4)3 counter-electrode is higher than that of a cell with the FeK[Fe(CN)6] counter-electrode.
Defect States in n-Type Germanium Irradiated with 1.5 MeV Electrons
Authors: Fukuoka Noboru , Saito Haruo
Published: November 2005

The defect levels produced in antimony- or arsenic-doped germanium by irradiation with 1.5 MeV electrons and the annealing behaviour of these materials were studied by the DLTS technique.
The position of the levels formed by radiation-induced defects was determined and the dependence of the level position on the species and concentration of the impurity atoms are reported. The defects associated with the E
c–0.40 eV level and the E
c–0.23 eV level are thought to be formed by the association of antimony atoms with unidentified defects.
From the results of annealing under injection, the defects associated with the E
c–0.23 eV level are considered to be annealed by a recombination-enhanced mechanism.
XPS and AES Studies on the Oxidation of Layered Semiconductor GaSe
Authors: Iwakuro Hiroaki , Tatsuyama Chiei , Ichimura Shoji
Published: November 2005

We have studied the oxidation of layered compound GaSe with no dangling bonds on the cleaved surface using XPS and AES techniques. At room temperature, the cleaved surface is not oxidized in an oxygen atmosphere. When subjected to Ar ion sputtering, the surface starts to exhibit the behavior of metallic Ga owing to dissipation of the first sublayer of Se in the primitive layer, Se–Ga–Ga–Se. The thin layer of metallic Ga thus exposed is easily oxidized. In the thermal oxidation of cleaved GaSe in air, the oxygen diffuses into the primitive layer and combines with Ga, severing the intralayer bonding between the Se and Ga atoms. At temperature higher than 450°C, the oxygen is also intercalated between the primitive layers from the sides perpendicular to the layers. No Se oxides are observed under any of the oxidation conditions.