An electron-beam-excited plasma (EBEP) apparatus produces high-density processing plasma. The plasma conditions are controlled by the parameters of the electron-beam source; discharge current (I_D) and accelerating voltage (V_A). As an instance of the applications, titanium nitride films are deposited as functions of I_D (3, 4, and 5A) and V_A (80, 90, and 100V) by ion plating technique under N₂ pressure of 0.1Pa. In this process, ion-beam is utilized in order to evaporate metal because ion current of the EBEP is high. Alumina (Al₂O₃), quartz (SiO₂), and silicon [Si(111)] of 10×10mm² are employed as substrates. The deposition time is constant of 1 hour. The films are evaluated from color, X-ray diffraction pattern, thickness and electrical conductivity. Regardless of substrate materials, the results are summarized as follows; (1) The deposited films consist of TiN and Ti₂N. (2) The formation of TiN becomes more dominant than that of Ti₂N as V_A increases, but changes little as I_D varies. (3) The film thickness increases as either V_A or I_D increases, and the values are up to 2μm.
Also, plasma condition is measured by spectroscopy, mass spectrometry, and Langmuir probe method. The results are surmarized as follows; (1) As V_A increases, N₂ dessociates, and then N⁺ in plasma markedly increases, but as I_D increases, the energy of particles in the plasma changes little. (2) The plasma density increases as either V_A or I_D increases.
From these results, it is found that the film composition and the deposition rate depend on the energy of particles in the plasma and the plasma density, respectively.

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To calculate nonlinear magnetostatics a new vector element in the volume integral equation has been developed. The magnetization vector in an element is expressed by using co- and contra-variant vectors corresponding to the each surface of the hexahedron element. To accelerate the conversion process, the iteration procedure has been divided into initialization and convergence parts. The method has been applied to TEAM workshop problem 13 of IEEE. Its calculated results agree with the measured data within 2%, indicating hod providesthe met good accuracy.

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Under the condition of high E/n, it is expected that electrons and ions gain very high energy. These charged particles with high energy may be utilized for processing of solid surfaces. Some analyses have been carried out to know energy distribution in discharges under high E/n condition. The authors have been calculated energy distributions of electrons and ions using the Monte Carlo method. Self-consistency was satisfied on calculated results till now. However, details on mechanisms to sustain discharges at the condition were not discussed. In this investigation, the electrode effect such as γi using the Δt method was analyzed and discussed. First, contribution of reflected electrons at the anode surface on electron multiplication process was calculated. Second, secondary electron emission coefficient γi at the cathode was evaluated and reasonable magnitudes were obtained on parameter at the anode. It is suggested from these results that reflected electrons at the anode give much influence on maintaining the steady state discharge at high E/n condition.

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Athermochargeable galvanic cell with a ferro-and ferricyanide ion redox couple incorporating a cation-exchange membrane and an extra pair of electrodes on each side of the membrane was fabricated and its thermocharge and discharge characteristics were investigated. The thermoelectric power of the experimental cells was more dependent on the distance between the main electrodes than on the ferro- and ferricyanide ion concentrations in the electrolyte. The thermocharge and discharge capacities increased with an increase in the ion concentrations. The ratio of the measured capacity to the capacity calculated from the ion concentrations also increased with an increase in the concentrations, although it was only at most 13%. The cell showed good thermocharge and discharge cycling performance: cycling at 0.5mA/cm² repeated 226 times until the capacity reached half of the maximum. This means that the ferro-and ferricyanide ions were used 10.5 times for 226 cycles.

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In order to investigate effects of high magnetic fields on the primary process of photochemical reactions such as hydrogen abstraction and electron transfer reactions, a laser flash photolysis apparatus equipped with a pulse magnet was developed. The magnet system consisted of a home-made solenoid coil(9.74mH)and a capacitor bank(4mF, 5kV, 50kJ). The full width at half maximum of the pulsed magnetic field was ca. 13ms and its maximum strength was 20T at room temperature. The laser flash photolysis system was composed of a pulse laser and a Xe arc lamp as excited and probe light sources, respectively, and a streak scope. The advantage of this pulsed magnetic field-laser flash photolysis apparatus is that transient absorption and emission of the short-lived radical intermediates can be measured in solution at room temperature even upon single laser pulse. Magnetic fic1d effect (MFE) upon photolysis of benzophenone in aqueous Brij35 surfactant solution was studied by using this new apparatus. As increasing the magnetic field intensity, the decay rate of the radical pair was retarded below 2T, while it was accelerated at 2-14T.
The inversion of MFE was ascribed to anisotropy of electron g-value of the radicals.

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Pressure change after arc ignition in a vacuum arc apparatus for TiN film deposition is measured for various pairs of N₂ flow rate (1-50ml/min) and initial pressure (0.01-10Pa). It is found that, after the arc ignition, in some cases the pressure converges to a certain value (operating pressure) and the arc steadily lasts, and in other cases the pressure continues decreasing until the arc self-extinguishes. For instance, at an initial pressure of 10Pa and an arc current of 50A, the arc lasts when the flow rate is more than 8ml/min, but the arc self-extinguishes when the flow rate is less than 8ml/min.
The pressure change is measured while the arc is ignited, sustained for 5min and extinguished. The result is interpreted with a model expressed by N₂ flow rate, evacuation rate, Ti evaporation rate, Ti deposition rate and N₂ fixation rate (rate of N₂ fixing to anode surface). From the relation among evacuation characteristics of the vacuum system, the initial pressure and the operating pressure, N₂ fixation rate is obtained as a function of the arc operating pressure. It is found that the N₂ fixation rate of 50 A is constantly about 8ml/min for the pressure range from 0.1 to 10Pa.
It is cleared from above two experiments that the arc is able to be sustained only when the N₂ flow rate is higher than the N₂ fixation rate.

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A precise measuring system based on the least squares method is developed for audio frequency voltage. The system consists of an analog-to-digital converter and a personal computer. An unkown voltage applied to the system is converted into discrete data with the usual sampling method or the frequency compressed sampling method, and precisely expressed as a polar vector by means of the least squares method. Some basic properties of the system, such as accidental errors of parameters estimated by the least squares method, effect of asynchronous sampling and frequency characteristics are studied. Thus, it is estimated that the unknown voltage of about 5 Vms is measured with standard doviation of 5×10^-5 in magnitude and 5×10^-5 rad. in phase angle in frequency range of 10 Hz‾100kHz.
This voltage measuring system is applied to compose a voltage ratio measuring system for ratio measurement of two voltages of a frequency. The system consists of a pair of the voltage measuring systems. The specific errors, namely systematic errors of the system are easily eliminated from each measured values by self-calibration. It is estimated that uncertainties of measured values are 5×10^-5 in magnitude and 5×10^-5 rad. in phase difference in frequency range of 10Hz‾100kHz, when two voltages of 5Vms are compared by this system.

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An airless nozzle equipped with induction charging electrode is useful to produce the space charge cloud consisting of highly-charged droplets. To estimate and to increase the charge density of the space charge cloud, a model of the space charge cloud in a cylindrical grounded electrode is proposed including the effect of not only drift of charged droplet in radial direction due to the electric field but also the deceleration in axis direction due to air resistance. The distribution of the charge density both inside and outside the droplets jet is deduced by the method of characteristics, solving Poisson's equation. In order to confirm the characteristics evaluated from this model, a space charge cloud was formed experimentally using the charged-droplet jet ejected from straight type airless nozzle and the electric field intensity and the charged droplet current were measured at the surface of the cylindrical electrode of 4m long and 1m in diameter. Experimental results agree with calculated ones. It was found that increase in the rate of deceleration of the droplets jet and decrease in their mobility were quite effective to increase the charge density of the charged droplet cloud.

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This paper describes the experiment of plasma formation and heating in the open air by superpotion of microwave and XeCl excimer laser beam as a fundamental study for Laser Triggering of Lightning. This experiment shows that a plasma can be formed by superposition of XeCl laser beam and microwave, and that continuous microwave can heat a laser plasma and can make it steady-state and big.
By superposing microwave on XeCl laser, the threshold value of XeCl laser energy for plasma formation is reduced to 20%. On the other hand, by superposing XeCl laser beam on microwave, the required power of microwave for plasma formation is reduced to 8%. Thus, superposition of XeCl laser and microwave will work effective for plasma formation and for triggering of lightning.

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The authors have been investigating the electric field-induced motion in mineral oil between plane parallel electrodes after change of electrode polarity. In this paper, the influences of electrode spacing on the motion are reported. Experiments were carried out under two conditions. The first condition was able to accumulate in the vicinity of electrodes all of the charge carriers existing in the oil between electrodes. The second condition was able to accumulate the quantity of charge carriers limited to the magnitude of charging voltage. We used the oils of electric conductivity 4.0×10^-14S/m and 8.9×10^-13S/m and observed time dependence of current and schlieren images of the motion for a range of elerctrode spacing extending from 2.5mm to 025mm at ±0.2MV/m.
The results are as follows: (1) In the cace of the first condition, time when current starts to increase and time for peak current shorten With the increase of the electrode spacing. (2) ln the case of the second condition, these times hecome long with the increase of the electrode spacing. (3) The motion produces a peaked behaviour in the current waveform without distinction of the accumulative condition of charge carriers. (4) The experimental results are well explained by established model.

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This paper describes the influence of gamma-rays irradiation on tracking failure of organic insulating materials by use of the LEC Publ. 112 method. Tracking resistance of organic insulating materials under wet polluted condition has been studied by many investigators with a test method of the IEC Publ. 112. The investigations on irradiation effects on tracking resistance should be enhanced due to the increasing usage of organic insulating materials in the radiation environments. The tracking resistance seems to be affected by gamma-irradiation, but the knowledge on the influence of gamma-irradiation is quite a few and systematic studies are needed. In this paper, modified polyphenylene oxide, polybutylene naphthalate, modified polycarbonate and polybutylene terephthalate which were irradiated in air until 1×10⁷R and 1×10⁸R with dose rate of 10⁶R/hrusing⁶⁰Co gamma-source have been employed. The total dose effects on the number of drops to tracking failure, contact angle and charges of scintillation have been studied. As the total doses are increased, the number of drops to tracking failure decreases with polybutylene terephthalate. On the other hand, the number of drops to tracking failure increases with polybutylene naphthalate and modified polycarbonate when the total doses are increased. The effects of gamma-rays irradiation on tracking failure are due to radiation-induced degradation or cross-linking of organic insulating materials. When the organic insulating materials are degraded by gamma-irradiation, the tracking resistance decreases, but for cross-linking type materials, the tracking resistance increases.

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Oxygen concentration in silicon Wafers has been determined by infrared emissivity measurement. As for the five measured samples, CZ silicon wafers with oxygen contents ranging from 3 to 10× 10¹⁷cm^-3 and thickness of 2.0 and 0.6mm were prepared. The good relationship for the oxygen concentration and the infrared absorption coefficient in each silicon wafer has been obtained between the differential transmission spectra and the defferential emissivity spectra. Moreover, it was clarified the emissivity measurement needed the calibration for lattice vibration absorption αe at a measured temperature for its accuracy.
In the results, the emissivity measurement showed its capability of the quantatitive method for the oxygen concentration and absorption in a silicon wafer. Therefore, this method seems to be effective for the half polished thin wafer-sized samples.

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