bluuebunny/crossref_metadata_2025 huggingface dataset:
Silicon Nitride Produced from the Stain Films on Silicon
Authors: Yamazaki Shumpei , Kato Yogoro , Okamoto Tomohide , Taniguchi Ichiro
Published: November 2005

Stain films are prepared on silicon substrates by the reaction between silicon and mixed gas consisting of hydrogen fluoride, nitric oxide and argon, Many fee silicon atoms in the stain films are chemically unstable, and changed into silicon nitride by the nitrogenation with ammonia at the temperature of 700°C to 1100°C. The stain nitride films made from the stain films on silicon have the initial V

F
B
from 1 to 3 V and N

F
B
of the order of 1010 cm-2 V-1. Resistivities, however, are from 106 to 109 \varOmega cm. When tow-layer silicon nitride films are prepared consisting of the stain nitride films and the deposited silicon nitride films by a gas phase reaction, the resistivities are improved and become 1×1014∼5×1014 \varOmega cm. Both the initial V

F
B
and N

F
B
remained unchanged or showed little increase.
Au-Ag Alloy-Silicon Schottky Barriers
Authors: Arizumi Tetsuya , Hirose Masataka , Altaf Nassem
Published: November 2005

Thin films of gold-silver alloy on n-type silicon were prepared by vacuum deposition of the alloy. The characteristics of the contacts were investigated by means of V-I and C-V measurements. The results showed that the barrier height of Au–Ag alloy–Si contacts varies linearly, from 0.67±0.02 eV to 0.80±0.02 eV, with composition of the alloy film. This is interpreted in terms of the change in work function which is linearly dependent upon the composition.
Holographic Generation of Contour Map of Diffusely Reflecting Surface by Using Immersion Method
Authors: Shiotake Norio , Tsuruta Tadao , Itoh Yoshinobu , Tsujiuchi Jumpei , Takeya Naoya , Matsuda Kiyofumi
Published: November 2005

This paper describes the double exposure holographic formation of a contour map over a diffusely reflecting or transmitting of arbitrary shape and surface finish by using an immersion method with media of different indices of refraction between successive exposure. A wavelength λ effectively contributing to the fringe contour is given by λ0/Δ
n where λ0 is the wavelength of the laser and Δ
n is the index variation. Index variations were introduced by pressure difference in Freon to give λ=600 µ and 200 µ, and by the combination of two liquids to give 14 µ and 25 µ, thus extending the change of height corresponding to each fringe contour continuously up to one thousand times greater than with the optical Fizeau fringes. A correcting plate of a Schmidt camera in the grinding process was used as a test object and its figuring error were analyzed.
Doppler Broadening of Helium Ion Lines in a Low Pressure Helium Arc
Authors: Okazaki Kiyohiko , Andō Kōzō
Published: November 2005

Profiles of Spectral lines emitted from a plasma in a low pressure helium arc which has an electron temperature of about 105°K and an electron density of about 1014 cm-3 have been studied. The results show that the measured profile of HeII 4686 Å can be well explained by Doppler broadening if the fine structure is taken into account. The apparent half-widths of HeII 4686 Å and HeII 3203 Å are shown in a figure as a function of the Doppler half-width of a fine structure component. The profile of HeII 3203 Å is mainly formed by Doppler broadening but Stark effect contributes to it by a few percents.
Investigation of Plasma Expansion in a Uniform Field and Shock Formation due to a Magnetic Barrier
Authors: Miyoshi Yasunori , Okamoto Yukio
Published: November 2005

Behavior of plasma expanding along a uniform guide field and the thermalization processes of the kinetic energy of the plasma flow by shock wave due to a magnetic barrier are investigated with the parameter of initial plasma. Longitudinal expansion of a plasma in a uniform guide field is accompanied by a decrease in the density and the temperature. The decrease in the temperature is smaller than the density decrease. This seems to be in agreement with a model, which has been applied on Bille en Têté experiment. Shock wave propagates in the upstream direction accompanying the in creasing of the temperature and the density behind the shock front. This phenomenon is clearer in the case of lower density and higher temperature plasma.
A Device for Measuring the Linear Compressibility of Solids
Authors: Tatsumoto Eiji , Okamoto Tetsuhiko , Fujii Hironobu , Ishida Junji
Published: November 2005

A small device usable under hydrostatic pressures and named “compressimeter” was developed for measuring the linear compressibility of solids. The compressimeter employs a strain gauge technique with an unbonded straight Advance wire, 0.026 mm in diameter and 40 mm in length. It has many advantages that the sample is easily replaceable, the Advance wire is unnecessary to be renewed whenever the sample is replaced, samples of small size can be used, and the measurement is possible over a comparatively wide temperature range. The theory, design and procedure of the compressimeter, and some results obtained are discussed.
Impulsive Plasma Produced by a Coaxial Plasma Gun
Authors: Hirano Katsumi , Irisawa Juichi , Nakano Yoshiei
Published: November 2005

This paper is concerned with an impulsive plasma mass produced by a coaxial plasma gun. According to spectroscopic observation the following results have been obtained. When the plasma is produced with an oscillatory current, the gun ejects more than two plasma masses successively. Except the first one they consist mainly of impurities. Spectral lines from helium are recognized only in the first mass. When plasma is produced with a single pulsed current produced by a crowber action, only one plasma is ejected and the succeeding impurity rich plasma masses are almost eliminated.
Rolling Friction of Metals
Authors: Minato Kikuwo , Nakafuku Chitoshi , Takemura Tetuo
Published: November 2005

Theoretical equations of rolling friction coefficient of metal by the rigid pendulum method were obtained as a function of dynamic mechanical properties of metal for the case of cylinder and sphere as follows, λ
c
=3k/2π(3/2)1/3tan
δ(W/E
1(ω))1/3
r
-2/3 and λ
s
=128k/15π2(4/π)1/4tan
δ(W/E
1(ω))1/4
r
-3/4, respectively, where tan
δ is the mechanical loss, E
1(ω) the Young's modulus, W the load, r the radius of roller and k the adjusting parameter. In the case of no micro plastic deformation due to adhesion these equations have good agreement with experiments over a wide temperature range by putting k=1/2 (this is the case of a continuous one dimensional generalized Voigt model). In the case of some micro plastic deformation, however, the experimental value of friction coefficient increases to the case of k=2.
Error Evaluation on Multi-Detector Methods in Neutron Measurements
Authors: Ryufuku Hiroshi , Nakayama Takashi
Published: November 2005

It is possible by introduction of `characteristic functional' K[φ] to evaluate errors due to the approximation using multi-detector methods in measurements of neutron dose equivalent rate, and to show them in a figure in a simple manner for arbitrary spectra. Dose equivalent rate is given by D=K[φ]N
1, where N
1 is the counting rate of one of the detectors. The maximum errors are determined by obtaining the maximum and minimum values of K[φ] represented in terms of the ratios of counting rates. Examples are given for two- and three-detector methods. Also, good approximations in the multi-detector methods are described by the use of the characteristic functional.
Anisotropic Hyperfine Constant in ESR Spectrum of Irradiated Solution Grown Polyethylene
Authors: Shimada Shigetaka , Kashiwabara Hisatsugu , Sohma Junkichi , Nara Shigeo
Published: November 2005

ESR spectra from the alkyl type free radical, –\underset(β)CH2–\underset(α)CH–\underset(β)CH2– , produced in irradiated crystals of high density polyethylene (Sholex 6000) grown from 0.025 wt. percent solution in xylene were studied, and anisotropic hyperfine splitting due to α-proton was investigated. Hyperfine splitting due to α-proton, D
α, was obtained as

|D
α|=24-5(1-3cos
2ψ)

in the unit of gauss, where ψ is the angle between external magnetic field and the direction of the c-axis of the molecule. Spin density at the carbon atom bearing the unpaired electron was calculated as 0.7 from analysis of the data of the spectrum for the mat of crystals. From the observed ESR spectrum for the alkyl type free radical produced in melt grown crystals, principal values of hyperfine coupling tensor were also estimated as follows; |A

z
|=13.6 gauss, |A

x
|=26.0 gauss, and |A

y
|=40.6 gauss. These values are very close to the calculated values.
Large-Signal Computer Simulation of Silicon p-i-n Avalanche Diodes
Authors: Matsumura Masakiyo
Published: November 2005

Large-signal oscillation dynamics of silicon p-i-n avalanche diode was computed. A large-signal conductance takes a negative value only near the Read frequency. Near this frequency, the p-i interface is equivalent to the avalanche region of the Read diode and the i-region except near the p-i interface is equivalent to the drift region of the Read diode. Segregation of such two regions as the Read diode is due to a difference of saturated velocity as well as of the ionization coefficient between electrons and holes. The oscillation dynamics under high dc current density condition is almost identical to that of the same oscillation frequency under low dc current condition.
Evaluation of Numerical Filters for Smoothing Spectroscopic Data
Authors: Yamashita Katsuji , Minami Shigeo
Published: November 2005

In recent years, numerical filtering is often used for the smoothing of spectroscopic data. This article is concerned with the computer analysis of numerical filters to find their optimal setup for spectroscopic measurements. Gaussian and Lorentzian contours are assumed for shapes of input signals to the filter in consideration of spectroscopic measurements. The distortion of the signal waveforms and the output noise levels are computed for the input data contaminated with the white or correlated noise. From the computed results which are summalized in the graphical presentation, optimal operating parameters of the data source and the succeeding filtering system are easily determined.
Temperature Dispersion of Complex Piezoelectric Modulus of Wood
Authors: Fukuda Eiichi , Date Munehiro , Hara Kiyoshi
Published: November 2005

Experimental technique for determining the ratio of piezoelectric polarization to the applied sinusoidal stress as well as the phase angle between them is described. The real and imaginary components of the complex piezoelectric modulus d=d'-j
d'' were determined for a few kinds of wood in a temperature range from -170°C to +150°C at a frequency of 20 c/s. In the vacuum dried specimen, d' gradually increased with temperature and the polarization lagged behind the stress. In the specimen including moisture, the piezoelectric moduli showed troughs at the room temperature range with the rise of temperature and the phase or the polarization led beyond the stress. The maximum of d'' at about -100°C was ascribed to the sum of viscoelastic loss and dielectric loss. The minimum of d'' at room temperature was accounted for by the dielectric loss due to the leakage current by moisture surrounding the piezoelectric cellulose crystallites. A simple model for explaining the piezoelectric dispersion is proposed.
Amplification of Neutral Acoustic Waves in Gaseous Plasmas
Authors: Ishii Tadao , Inuishi Yoshio
Published: November 2005

The amplification of neutral acoustic waves is investigated in gaseous plasmas consisting of three species of particles (neutral, ion, electron). The calculatoins are done on the basis of the two kinds of assumptions: (1) The ion+neutral system is regarded as a continuous medium and is approximated by an elastic wave equation, (2) each of systems (electron, ion, neutral) is treated hydrodynamically using Euler's equations. The two amplification constants obtained from the assumptions (1) and (2) are both the linear function of the electron drift velocity. The case (2) gives more strict informations than the case (1). The former is in more qualitative agreement with the experimental findings of Yatsui et al.,2) provided that an injection of ultrasonic waves increases the collision frequency of the systems.
Surface Charge Wave Propagation and Proposed Devices
Authors: Toda Minoru , Tosima Soitiro
Published: November 2005

The properties of surface charge waves drifting on two sheets of semiconducting films were investigated theoretically by solving the Poisson's equation with a practical boundary condition. The analysis was done for two configurations. One, for a tapered dielectric thin film sandwiched between two semiconducting films and the other for a thin dielectric film with a nonuniform dielectric constant sandwiched between two sheets of semiconducting films. Calculations showed the propagation power should increase when the distributed capacitance between the semiconducting films gradually decreased in the propagation direction, even for a constant amplitude of the surface charge wave. When the distributed capacitance is uniform, a negative differential conductivity in the semiconductor is shown to give energy to the surface charge wave and the growth rate was shown to be smaller than that for bulk space charge in usual GaAs devices. The transit time effect or the surface charge wave has been found to produce an inductive impedance for a semiconductor film over a certain range of the transit angle.
Duration of the HCN Laser by Pulsed Discharge in a Seal-Off Tube
Authors: Murai Akira
Published: November 2005

This paper is concerned with a long time operation of HCN far infrared laser oscillation. The laser oscillation has been conventionally obtained by means of a flow method. On the contrary, the pulsed oscillation was performed in a seal-off tube in the present study. A weak but stable 337 µm oscillation continued for a long time up to 70 hours in gas mixtures of BrCN+H2 or BrCN+CH4, and a strong oscillation in C6H6+N2+H2+Br2 and CH2Br–CH2Br+N2+H2 with a duration of 1 to 4 hours. Replacement of H by D did not give a long time operation. The role of bromine in the maintenance of oscillation will be discussed briefly.
Experimental Studies on the Limitation of Focussing Power of Hyperbolic-Type Gas Lens
Authors: Iga Ken-ichi , Suematsu Yasuharu
Published: November 2005

The focussing effect of Hyperbolic-type Gas Lens which was proposed by the authors for light beam waveguide is examined experimentally. Six types of experimental gas lens with different separation of poles 2a are made, and the temperature distribution on the heat conductive poles and in the gas medium is measured. The focussing characteristics of these types of gas lens are examined using the Gaussian light beam from a He-Ne gas laser. It is concluded that the focussing power is limited by the natural convection of the gas when the temperature difference between the poles is increased, and it is found that the critical temperature difference 2Δ
T

c
above which the gas lens does not work normally is determined only by the separation 2a between the poles. The relation between them is formulated experimentally as follows;

ΔT_c\cong42/a^1.34,   20\gtrsima\gtrsim5 (mm)ΔT_c\cong83/a^1.74,   2\lesssima\lesssim5 (mm).

This formulation serves as the data for the design of the waveguide using this tpye of gas lens.
The Contrast of Electron Microscope Images of Thick Crystalline Object. Experiment with an Al-Mg-Si Alloy at 50-100 kV.
Authors: Sahashi Toshio
Published: November 2005

The deterioration of the quality of electron microscope images with the increase of specimen thickness was studied at 50, 80 and 100 kV. The specimen used was an Al-Mg-Si alloy which has linear-precipitates along <100> directions in the aluminium matrix. The images of the precipitates became invisible at 0.9, 1.4 and 1.7 µm at 50, 80 and 100 kV, respectively. The width of the images increased with the specimen thickness. However, the increase was much smaller than that calculated by use of the current formula of the chromatic aberration. The images became invisible due to the decrease of contrast. These results are explained by a detailed treatment of the chromatic aberration.
Si- and Ge-Doped GaAs p-n Junctions
Authors: Moriizumi Toyosaka , Takahashi Kiyoshi
Published: November 2005

Si- and Ge-doped GaAs layers were obtained by a solution regrowth technique. They were p-type and their electric parameters ρ, µ
H
, and p were found depending on the Si or Ge quantities in the melts. Ge-doped crystals had much larger µ
H
values than Si-doped crystals. Si-doped p-n junctions showed I-V characteristics including tunneling and thermal components, while those of Ge-doped junctions had only a thermal component. Si-doped diodes showed photo responses originating from deep acceptor levels, while the photoresponses of Ge-doped ones were derived from a very shallow acceptor level. The same effects were seen in the emission spectra of these diodes. In the Si-doped ones, broad emission peaks were found at the longer wavelengths on account of the deep levels, while the emission spectra of Ge-doped diodes were sharp and concerned with the shallow acceptor level. An emission quantum efficiency of up to 2% was achieved in the Si-doped diode.
Ceramic CdS Solar Cell
Authors: Nakayama Nobuo
Published: November 2005

This paper describes the properties and the model of ceramic CdS photovoltaic cell made by treating CdS ceramic plate electrochemically in copper ion solution. The compositions and structures were analysed by means of X-ray Ginuie Camera and X-ray microanalyser.
It was found that Cu2-x
S (0≦x≦0.2) is formed along grain boundaries over a range of a several ten microns of the surface layer, and that the photovoltaic junctions exist at grain boundaries in this surface layer.
From examinations of the voltage dependence of the barrier capacitance, the junctions could be classified into step junction, graded junction and Mott barrier, according to the prepared method. The spectral response measurement indicates that the origin of the photo-emf of the Mott barrier is mostly impurity photovoltaic effect.
Avalanche Breakdown Voltages in Punch-Through Si Epitaxial Planar Schottky Barrier Diodes
Authors: Kano Gota
Published: November 2005

Avalanche breakdown voltages in punch-through epitaxial Schottky barrier diodes have been calculated by the computor more fundamentally than previously reported by the author. And the experimental results obtained in this paper by introducing a new technique–Insertion of Channel-Stopping Guard Space–have approached to this theoretical limit.
Strain Measurement by Optical Differentiation of Cross Grating
Authors: Iwata Koichi , Nagae Sadahiko , Nagata Ryo , Okuno Genjiro
Published: November 2005

A method for measuring three strain components from a single plane specimen is presented, where the strain distributions induced in the specimen are transformed into light intensity distributions. The optical differentiation with a cross grating is adopted for this purpose. The theory and the experimental result are shown.
Some consideration on the comparison with other methods for measuring two-dimensional strain distribution and future possibility of this method are discussed briefly.
Undulation in the Output of a Pulsed Water-Vapor Laser
Authors: Kasuya Takahiro , Shimoda Koichi , Takeuchi Nobuo , Kobayashi Shunsuke
Published: November 2005

Output waveforms of a pulsed H2O laser are observed with an indium-doped germanium detector. The waveform is subject to a remarkable undulation and its frequency varies with the discharge current and conditions of the resonator rather than with the wavelength of emission. It is found that the undulation is interpreted as the beat between laser oscillations of different transverse modes. Since the maximum electron density of order 1012 cm-3 in the laser tube produces a change in refractive index of order 10-6 in the far-infrared, the radial distribution of the electron density is responsible for the change in beat frequencies between transverse modes. Effects of the electron plasma in the optical resonator are theoretically given and applied to explain the observed results.
Reproducibility of the Boiling Point of Oxygen and Its Pressure-Temperature Relation near 1 Atmosphere
Authors: Mochizuki Takeshi , Sawada Shigeaki , Takahashi Masato
Published: November 2005

The accuracy of the realization of the oxygen point has been investigated through calibration of two platinum resistance thermometers of capsule type against the vapour pressure of oxygen of which the purity has been strictly checked. From 65 measurements ranging from 660 to 860 mmHg of pressure, the International Practical Temperature t
int,1948 has been found to be expressed by
t
int,1948=-182.97+9.5425(p/p
0-1)-3.686(p/p
0-1)2+2.28(p/p
0-1)3

where p
0 is 1 standard atmosphere, and the reproducibility attained has been ±0.00022 degree in terms of the standard deviation. The interpretation of the same data in the CCT64-scale of temperature is also given. Although the temperature value derived from resistance thermometers depends slightly on the characteristics of thermometers in use, it is concluded that the equation derived here are more accurate than that given in the text of the IPTS 1948.
Mean and Anomalous Absorption Coefficients of Electrons for Magnesium Oxide Single Crystal
Authors: Ichimiya Ayahiko
Published: November 2005

Intensity profiles of electron microscopic images formed by elastically scattered electrons were analyzed for three different diffraction conditions: (1) The incident beam is parallel to the (100)-plane, (2) No Bragg reflection is excited and (3) (200) Bragg reflection is at the exact Bragg condition. Accelerating voltages were 50, 75 and 100 kV. Inelastically scattered electrons were eliminated by Ichinokawa's magnetic velocity analyzer. The absorption coefficients were determined by comparison of the observed intensity profiles with those calculated by the formulae of h00-six-beam approximation. The result showed that the mean absorption coefficient is µ0=1.5×103Å-1, and the anomalous absorption coefficient is µ200=0.24×10-3Å-1 at 100 kV. Both of µ0
-1 and µ200
-1 were approximately proportional to the square of the electron velocity. Intensity profiles of ordinary images are explained by basis on the results for elastically scattered electrons.
Effects of Crystallographic Orientation on Mobility, Surface State Density, and Noise in p-Type Inversion Layers on Oxidized Silicon Surfaces
Authors: Satô Tai , Takeishi Yoshiyuki , Hara Hisashi
Published: November 2005

Experimental results are reported concerning the anisotropy of surface state density, N

s
s
, 1/f-type equivalent noise voltaze, V

N
, and field effect mobilitv, µ
F
E
, in p-channel MOS transistors with various crystallographic orientations in <011> and <001> zones. The amounts of V

N
and N

s
s
are strongly correlated to each other, and both appear to be smallest around (811)-oriented surfaces. µ
F
E
under strong electric field normal to the surface shows no apparent correlation to N

s
s
, but is markedly dependent on the direction of current flow on each surface except (111) and (100): µ
F
E
is maximum in the direction parallel to [011̄] on (011) plane and µ
F
E
⊥[011̄] is higher than µ
F
E
//[011̄] on the planes between (111) and (100). The mobility anisotropy is interpreted in terms of the effective mass anisotropy caused by quantized hole motion, considering that the energy band structure at high energy remarkably differs from the one at lower energy.
Transitions and Phases of Polytetrafluoroethylene
Authors: Hirakawa Susumu , Takemura Tetuo
Published: November 2005

Behavior of transitions and the nature of high-pressure phase in polytetrafluoro ethylene are studied using methods of ultrasonic waves, thermal expansion, differential thermal analysis and X-ray diffraction. A phase diagram is obtained in pressure range from 1 atm. to 6,500 kg/cm2 and in temperature range from room temperature to 165°C. Three phases are found; phase I above 30°C, phase II below 20°C, both at 1 atm. and phase III above 5,000 kg/cm2. The triple point is located at 75°C and 5,000 kg/cm2. Pressure dependence of transition temperatures is obtained as 15 and 9 degrees per 1,000 kg/cm2 for the 20°C and 30°C transitions at low pressure, 9 degrees per 1,000 kg/cm2 for both transitions at intermediate pressure range from about 3,000 to 5,000 kg/cm2, -13 and 50 degrees per 1,000 kg/cm2 for the II–III and the III–I transitions, respectively. It is suggested that the high-pressure phase (phase III) may be a closely packed but disordered phase.
Electrical and Optical Properties of Sputtered CdO Films
Authors: Tanaka Kuniaki , Kunioka Akio , Sakai Yoshio
Published: November 2005

CdO films were prepared by a D–C reactive sputtering method with various sputtering voltages. The characters of the prepared films are compared with the reflection electron diffraction and X-ray diffraction patterns. Especially, the effects of the sputtering voltage and partial pressure of oxygen were investigated concerning the electron densities and the Hall mobilities. The observations on lattice parameters lead to the conclusion that CdO films with high carrier concentrations contain some amount of interstitial excess Cd atoms. The absorption edge variation of annealed films prepared by high voltage sputtering agrees with the theoretical curve which is accounted from the Fermi level shift caused by the change in carrier concentrations.
Contact of ZnO Thin Films with Rhodamine B Dye
Authors: Niikura Ikuo , Watanabe Hideo , Wada Masanobu
Published: November 2005

In order to explain the mechanism of dye sensitization on a photoconductive semi-conductor, the changes of the conductance of ZnO thin films due to the contact of Rhodamine B layer under various states of oxygen desorption were measured. The experimental results seem to show that transfer of electrons between ZnO thin film and the dye layer takes place when the contact is made.
Thermal Diffusivity Measurements of Ceramics by a Modulated Electron Beam Technique
Authors: Serizawa Michiya
Published: November 2005

An experimental method is described for the determination of the thermal diffusivity by the measurement of the phase difference between the temperature fluctuations at two faces of a thin plate of material, where the applied heat by an electron gun is modulated sinusoidally. An approximate equation of the relation between phase difference and thermal diffusivity of ceramics has been obtained so that thermal diffusivity of ceramics can be measured at high temperature without direct measurements of heat loss parameters. The results for the thermal diffusivity and the thermal conductivity of MgO and UO2from 900°C up to 1,700°C were obtained by this method and apparatus with the estimated accuracy of ±10%. The measured thermal conductivities of MgO and UO2are in good agreement with the standard values.
Phosphorescence Decay of Benzophenone containing Naphthalene at 77°K
Authors: Nakamura Tokihisa , Hayakawa Sohachiro
Published: November 2005

Phosphorescence decay curves have been measured for benzophenone in the presence of various concentrations of naphthalene, at 77°K. Decay time of the phosphorescence of benzophenone was changed from 5 msec to 3 msec by changing concentration of naphthalene. A kinetic analysis of energy transfer in solid solutions has been carried out using benzophenone as the donor and naphthalene as the acceptor. From the decay data of benzophenone, 2.4×10-20 cm3 sec-1 has been obtained as the rate of excitation energy transfer from the triplet state of benzophenone to that of naphthalene. The effectiveness of zone purification process of benzophenone has been studied as well as the effect of doping naphthalene.
Note on Impurity Oxygen in Gallium Phosphide
Authors: Miyauchi Takeshi , Sonomura Hajimu , Yamamoto Nobuyuki
Published: November 2005

Zn-doped GaP crystals were grown from the solutions either in carbon-coated quartz containers or in bare containers. These sorts of crystals showed markedly different characteristics in the photo- and electroluminescences, namely, the crystals obtained from the bare containers emitted a red light (675 mµ) and a weak green light (560 mµ), while the crystals from the carbon-coated containers emitted the green light only. It has been concluded from these results that most of oxygen, an impurity in GaP, is introduced from heated quartz container during the fabrication of crystals and re-confirmed that the oxygen correlates closely with the red emission although its more detailed behaviour is not made clear yet.
Mechanism of Carrier Injection and Light Emission in Cd1-xMgxTe p-n Junctions at Room Temperature
Authors: Yamamoto Ryoichi
Published: November 2005

Electrical and electroluminescent properties in P-diffused Cd1-x
Mg
x
Te (x=0, 0.2, and 0.35) p-n junction diodes were measured at room temperature and are discussed in detail by using the theory for injection-recombination kinetics with emphasis on radiative recombination.
The I-V characteristics of these diodes show an exponential behavior of the form I=I
0exp
(q
V/m
k
T), where m=2 at low biases and m<2 at high biases. The change in the slope can be explained by the space-charge recombination current through deep centers. An analysis of the bias dependence of the light emission shows that the diffusion current dominates the current concerning radiative recombination.
Electronmicroscopic Observation of Print-Out Effect on AgBr Microcrystals
Authors: Iijima Sumio , Hibi Tadatosi
Published: November 2005

By using silver bromide microcrystals obtained from a high sensitive photographic film emulsion, the effects of the intensity of light source and the temperature of the specimen on the print-out effect of the silver bromide crystals were studied electron-microscopically. As a result, it was found that with increasing the intensity of light source or with raising the temperature of the specimen the density of the pits decreased and well-defined tri-pyramidal pits began to appear on the surface of the grain. Although triangular patterns were observed frequently on the surface of the grain at room temperature for weak light illumination, they decreased in number and became large in size with increasing the intensity of light source or with raising the temperature of the specimen. The protrusion and whisker of silver also appeared on the grain at an elevated temperature due to light illumination. Experimental results obtained are discussed.
Improvement of the Quality of Dark Field Images of Electron Microscope with the Increase of Accelerating Voltage
Authors: Sahashi Toshio
Published: November 2005

The dark field images of crystalline objects were taken at accelerating voltages, 50–1000 kV, with the incident beam parallel to the optic axis. Since the image forming ray makes a large angle, twice the Bragg angle, with the optic axis, the image quality is much lower than that of bright field images at ordinary accelerating voltages, 50–100 kV, due to the chromatic and spherical aberrations. It was shown experimentally that in high voltage electron microscopes (higher than 500 kV), both aberrations were much reduced and became almost negligible at 1000 kV for low order reflections.
Millimeter-Wave Photoconductivity and Donor State in N-Type InSb
Authors: Yamamoto Junya , Yoshinaga Hiroshi , Fujita Junji
Published: November 2005

N-type indium antimonide shows the photoconductive effect not only in the far infrared, but also in the millimeter-wave region. Millimeter-wave photoconductivity was observed in the 2 mm-wave region to clarify the origin of the effect. It is concluded that, in elements with low carrier concentration, the impurity transition between shallow donor levels is the main process for the photoconductivity, while the hot electron photoconductive effect is small as compared with the impurity photoconductivity. Performances as a millimeter-wave detector are also studied. Signal-to-noise ratio of InSb detector is superior to that of conventional silicon point contact diode. Rise and decay times of the detector without magnetic field are about 0.4 µs and 0.7 µs respectively. This detector is useful even for measurements of incoherent radiation.
X-Ray Diffraction Topography Utilizing Double-Crystal Arrangement of (+, +) or Non-Parallel (+, -) Setting
Authors: Kohra Kazutake , Hashizume Hiroo , Yoshimura Jun-ichi
Published: November 2005

A potential utility of the double-crystal arrangement of (+, +) or non-parallel (+, -) setting for obtaining a diffraction topograph is studied. The method is simple in mechanism and enables us to obtain well-defined images of imperfections from a large area of a specimen without any scanning mechanism in a rather short exposure time. Differing from the double-crystal arrangement of the parallel setting usually used, the present method allows us to obtain topographs for any reflection of any kinds of crystals irrespectively of the first crystal. For the first crystal is employed the asymmetric 111 reflection of a nearly perfect Ge crystal to take photographs from a large area in a rather short exposure time by using a usual sealed-off X-ray tube. As examples are shown some transmission topographs taken with Cubα1 from a LiF crystal, and Si web crystals as grown and after heat-treated.
Effects of Impurities on the Radiation Damage and Annealing Behavior of Si Solar Cells
Authors: Usami Akira
Published: November 2005

The reduction of minority carrier lifetime by γ-irradiation is strongly dependent on the sample type P/N or N/P, and the effect of chemical impurities such as Cu and Ni on radiation resistance is rather remarkable in N/P-type than in P/N-type samples. Introduction rate of defects for P/N and N/P-type cells contaminated with impurities decreases to about 1/2 and 1/7 of non-contaminated cell's, respectively. In N/P-type cells, the increase in short-circuit current under γ-irradiation is observed, and is due to an improvement of V-I characteristics. The isochronal annealing behavior of cells is also strongly dependent on the sample type. Annealing temperature for P/N-type cells contaminated with chemical impurity is lower than that for non-contaminated P/N-type. Impurity-contaminated cells showed a remarkable increase in unannealed fraction of short-circuit current over the temperature range of 180°C–200°C. For N/P-type cells, an abrupt increase in unannealed fraction is observed at about 120°C for both Cu-contaminated and non-contaminated cells.
Electrical and Optical Properties of Si-SnO2 Heterojunctions
Authors: Nishino Taneo , Hamakawa Yoshihiro
Published: November 2005

Electrical and optical properties have been investigated on Si–SnO2 heterojunctions. Semiconducting SnO2 film has been grown by a successive oxidation of the evaporated tin on the (111) surface of silicon single crystal. The SnO2 film shows the properties of a degenerate n-type semiconductor having the band gap energy of 3.5 eV. The current-voltage characteristics of Si–SnO2
n–n heterojunction represent a good rectification. The photovoltage measurements demonstrate that the Si–SnO2
n–n heterojunction has the photoresponse in the wide wavelength region from 400 to 1200 mµ at room temperature. The energy band diagram of Si–SnO2
n–n heterojunction is determined from the results of these electrical and optical measurements.
Simultaneous Oscillation of a He-Ne Gas Laser at 6328 Å and 3.39 µm
Authors: Nagai Haruhiko , Taniguchi Ichiro , Tomishima Kazunaru , Miyazawa Toshiko
Published: November 2005

Single-mode output power P at the center of a 6328 Å spectral line, when the laser oscillates simultaneously at both 6328 Å and 3.39 µm, is obtained by solving rate equations of a five-level system. P is calculated for several discharge currents as a function of the cavity detuning from the center of a 3.39 µm spectral line by using the unsaturated gain, total cavitv loss, and the single-mode output power at 3.39 µm. Good agreement between the calculation and the experimental results is obtained.
High-Speed Plasma Flow in a Cusped Magnetic Field
Authors: Tanaka Masatoshi
Published: November 2005

High-speed plasma flow, the flow velocity of which is much larger than the thermal velocity of the ions, in a cusped geometry is investigated. The density distribution of the plasma in a plane perpendicular to the axis is assumed to be known and the ions there to have a Maxwellian distribution of velocities. The ion distribution in the downstream is calculated in the free-particle approximation.
Observations of Dislocation Motion by Etch Hillocks in White Tin Single Crystals
Authors: Hirokawa Tomoo , Yomogita Kazuo , Honda Katuhiko
Published: November 2005

Pyramidal etch hillocks are produced on the {001} surfaces of 99.999% pure white tin single crystals at the sites of both fresh and aged dislocations with the highly selective etchant. Hillocks grow with a constant rate during the etching period. The growth rate of the edge length of a hillock is about 2.1×10-2 µ/sec. When the crystals are strained in the etchant, etch traces of hillocks are produced just along the loci of the moving dislocations. In this case, various modes of dislocation motion can be discriminated in moving direction, velocity and its variation from the appearances of traces.
Surface Electronic States and Field-Ion Image Intensity of Metals
Authors: Tamaki Shozo , Sugata Eizi
Published: November 2005

The variation of the regional image intensity with the applied voltage was measured for the (001), (011) and (111) planes of W and Mo tips in the field-ion microscope. As the result, it was found that the regional image intensity of (111) plane of W and that of (001) plane of Mo tips didn't increase monotonically with the applied electric field. Total image intensities for W, Mo, Ir and Re were also measured and it was found that they decrease in the order of Re, Ir, Mo and W.
Far-Infrared Difference-Frequency Generation by Picosecond Laser Pulses
Authors: Yajima Tatsuo , Takeuchi Nobuo
Published: November 2005

A method of far-infrared generation by optical difference-frequency mixing between the modes of a mode-locked laser has been studied both theoretically and experimentally. General formulae for the spectrum and the intensity of the beat radiation for both mode-locked and non-mode-locked inputs were derived. The generation of a broad-band far-infrared beat in the range of 1–20 cm-1was observed when the output of a mode-locked Nd:glass laser was incident on LiNbO3, ZnTe, ZnSe, CdS and quartz crystals without collinear phase matching conditions. The efficiency of beat generation was found to be enhanced by a factor of 10 due to mode-locking. The beat intensity and its anisotropy were measured for each crystal and were found to be in reasonable agreement with the theory. By using metal-mesh filters, a major portion of the beat energy was found to exist in the spectral region above 10 cm-1. The possibility of this scheme as a tunable submillimeter-wave source is discussed.
Nonexistence of Closed Flux Surfaces in a Magnetic Well
Authors: Sometani Taro , Yamamoto Kenzo
Published: November 2005

It is shown that the existence of closed magnetic or flux surfaces is impossible in a simple magnetic well where the field strength increases outwards in a monotone. If r is taken as a position vector from a certain fixed point in space to a moving point on a magnetic field line, the field strength increases in the direction opposite to r at the point where the magnitude of r is maximum.
Wired-Wall Cavity for V-Band ENDOR Experiment
Authors: Yagi Hisao , Inoue Masasi , Tatsukawa Toshiaki , Yamamoto Takamitsu
Published: November 2005

A so-called “wired-wall” cavity has been designed to make electron spin resonance (ESR) and electron nuclear double resonance (ENDOR) experiments in the V-band region (6 mm wavelength) at low temperatures. Attention has been paid on the microwave mode, the Q-value, the radio frequency (r-f) power supply for ENDOR, a magnetic field modulation, and the overall sensitivities. An attempt of ESR experiment was made on Mn2+ in MgO at room temperature by using this cavity. The maximum Q-value obtained was about 3,500. Sufficient r-f power for NMR could be supplied through a part of the wired-wall from 3 to 5 Watts in the frequency range 16–20 MHz. ENDOR experiment was also made on Cr3+ in Al2O3 (ruby) at liquid helium temperature.
Generation of High Intensity Beams of Nanosecond Pulse Duration by Electron Linacs
Authors: Irie Koichi , Uetomi Isamu
Published: November 2005

Acceleration of electron beams with a very short pulse duration and high peak intensity is achieved in electron linacs. As pulse generators for very short pulse duration, a coaxial line-type pulser, a hard-tube pulser and a pulse sharpener are newly developed which can produce pulses of about 5 nanoseconds in pulse duration and about a few thousands volts in amplitude in 50-ohm load. In Tohoku linac, peak intensity of 1.3 amperes is obtained with pulse duration of 7 nanoseconds and energy of 75 MeV, while in Mitsubishi linac, 2.0 amperes, 10 nanoseconds and 6.4 MeV, respectively. Their results agree with Leiss theory. As a parameter of transient beam loading, the ratios of the energy contained in a pulsed beam to the stored energy in the accelerating structure and of the peak beam power to the peak input RF power are presented.
The Effect of Gamma Irradiation on the Very Dilute Solution of Collagen in the Atmosphere of Air and Nitrogen
Authors: Kohno Kaku , Nishihara Tomio , Fukada Eiichi
Published: November 2005

Low dosage gamma-ray irradiation on very dilute solutions of collagen are investigated. Acid-soluble collagen extracted from calf skin are fully purified and dissolved into a 0.05% aqueous solution of acetic acid at a concentration of 0.021%. Gamma-ray irradiation with a dose rate of 4×102 r/min are given to the solution in the atmosphere of air or nitrogen. Irradiation in air up to 3×104 r produces about 70% decrease of intrinsic viscosity, about 20% decreases of optical rotation and of average molecular length estimated from flow birefringence, and noticeable lowering of denaturation temperature. The results suggest the occurrence of scission reactions in polypeptide chains in the triple helix of collagen molecule. On the other hand, irradiation in nitrogen up to 3×103 r causes about 20% decrease of optical rotation, about 20% increase of average molecular length, and remarkable increase of intrinsic viscosity. Gelation takes place at about 5×103 r. The results indicate the predominance of crosslink reactions during irradiation in nitrogen.
Studies on Chemisorption of Nitrogen on Tantalum with the Field Emission Microscope
Authors: Oguri Takeo
Published: November 2005

The chemisorption of nitrogen occurs on all crystal planes of tantalum and decrease the average work function as much as 0.00∼0.06 eV. Three multiplex states of chemisorption are found from the observation of the field emission pattern and the measurement of the work function change. The B
1-state exists on rough planes such as the (111) plane, vicinities of the (100) and (110) planes, and nitrogen chemisorbed at this state disappears below 620°K and increases the work function of these rough planes as much as 0.23 eV. The B
2-state exists on flat planes, that is, the (100) and (110) planes, and the B
2-nitrogen disappears below 970°K and lowers the work function as much as 0.42 eV. The B
3-state exists on rough planes such as the (111) plane and vicinities of the (211) and (111) planes, and the change of the work function caused by the B
3-adsorption is calculated as -0.05 eV. Nitrogen chemisorbed at this state begins to desorb at 970°K, and the desorption completes at 1370°K. The B
2-state is probably concerned with the direct absorption at its adsorption site.
New Method for Preparing Unusually Oriented Tungsten Tips and Their Growth Mechanism
Authors: Okuyama Fumio , Hibi Tadatosi
Published: November 2005

A new method for preparing tungsten tips having an unusual orientation, for example, the [100]- or the [111]-orientation, was studied by using a field emission microscope. It was found that tungsten tips having the [100]- or the [111]-orientation could be obtained with heat treatment of the tip at low temperature (1500°–2300°K) after introducing air or oxygen into the experimental tube. To make clear the mechanism of the change in the tip orientation from the normal orientation to the unusual one, light- and electron-microscopic observations of the cathodes were carried out. As a result, it became clear that the growth mechanism of the unusual tip could be explained by assuming that the tungsten tip rotated around a fixed <110>-axis under the tungsten carbide film so as to transfer to the stable state from a semi-stable state.
Getter-Bias Sputtering of High Purity Metal Films in a High Current Vacuum Discharge in the 10-4 Torr Range
Authors: Pinto R. , Shaha B. M.
Published: November 2005

It is shown that by using a Titanium getter high purity and uniformly thick refractory metal films could be deposited at a very fast rate by a high current vacuum discharge in the 10-4 Torr range. The system described is based on Gaydou's technique. Various discharge characteristics have been studied and the film purity has been estimated by calculating the specific resistivities of the films before and after artificial aging. The lowest specific resistivitv of Tantalum film deposited with a getter and a 100 V negative bias is 19.6 µ\varOmega-cm. Adhesivity and possible applications of Tantalum films in thin film hybrid technology have also been studied.
Information Capacity of Radiographic Images for the Random Signal and Continuous Objects
Authors: Kanamori Hitoshi , Murashima Sadayuki
Published: November 2005

Some of the results in a previous paper, JJAP 7 (1968) 414, which deals with the random signal are considered again. The capacity is roughly proportional to the square bandwidth of the equipment. The reason is explained. To investigate the decrease of the capacity of actual continuous object from the random signal, capacities for three kinds of object spectrum, including that of bones in human bodies, are estimated using numerical examples. For wide object spectra, the wider bandwidth of a radio-graphic or inspecting equipment produces the greater capacity. For narrow object spectra or for low frequency objects, the capacity is proportional to the square spread of the object spectrum and the insertion of a low pass filter improves the capacity. The reasons are discussed in detail. Since eyes and an intensifying screen act as low pass filters, for low frequency objects, the capacity of the film directly exposed is increased by exposing with the screen or by inspecting by eyes.
Diffraction by Circular Apertures with a Ring-Shaped π-Phase Change
Authors: Asakura Toshimitsu , Mishina Hiromichi
Published: November 2005

Expressions are given for the three-dimensional irradiance distribution of the error-free diffraction pattern by circular apertures with a ring-shaped π-phase change. Both the amplitude distribution in the focal plane and the irradiance distribution along the optical axis have been evaluated for a large number of cases. Some interesting results are discussed and illustrated graphically. The resolving power and focal depth are taken into considerations with these apertures. Finally, some experimental results are presented.
Particle Diffusion in a Low Pressure Crossfield Plasma Heating Device
Authors: Rikoski Richard A. , Young Frederick J.
Published: November 2005

The Slepian discharge rotating magnetoplasma is investigated in helium for neutral gas pressures of 3.3×10-1 and 6.7×10-2 torr with end wall potentials to +300 volts d. c. and an applied axial magnetic field of 0 to 6000 gauss. A cold cathode field emission Penning discharge radial ion source is incorporated within the apparatus as a central ion source.
Ion and electron diffusion rates across and along the applied field lines are determined as functions of applied end wall potential, Penning discharge current and axial field strength. For pressures of 3.3×10-1 and 6.7×10-2 torr, anomalous increases in radial current with increasing magnetic field are not observed, while distinct minima in end wall currents are found suggesting a critical value of magnetic field strength after which the character of the particle flow to the end walls markedly changes.