Plasma-based ion implantation technology has been developed for more than 15 years. Recently, the technology has been accompanied by deposition onto a substrate immersed in a metal or semi-metal plasma. The process using this hybrid system is actively researched for cost-effective and simple modification system, in particular, in Japan. Recent trend of plasma-based ion implantation and deposition from hardware of the apparatus to applications through fundamental researches is introduced in the article.

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We demonstrate the luminance control of organic electroluminescent (EL) device with indium tin oxide (ITO) treated by argon plasma, as a new patterned process to ITO substrate itself for producing the organic EL device under a continuous dry-process. The high-precision patterned image in the organic EL device was obtained. The sheet resistance of the ITO layer treated by argon plasma increased remarkably, although the work function of the ITO layer did not changed. The change in sheet resistance of ITO layer is attributed to changes in morphology of the ITO surface, i. e., structural modification by argon ion and electron.

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By using a newly developed simulation program "PEGASUS", plasma behavior was analyzed for the plasma immersion ion implantation and deposition (PIII&D). For plasma analysis of low pressure gas which is used in PIII&D, the software uses a particle in cell (PIC) method for the analysis of electric and magnetic fields and the motion of charged particles. A Monte Carlo collision method is used for collisions of ions, electrons and neutrals in the plasma, and the dynamic-SASAMAL code is used for the ion-solid surface interactions. Spatial distributions of potential, electron density and ion density together with the ion flux distribution on the target surface were calculated for the case where a negative pulse voltage was applied to a trench shaped target immersed in a high density Ar plasma (10¹⁰ cm^-3). The time evolution of sheath length obtained by the simulations for a flat plane part of the surface agreed with the analytical result obtained by the Child-Langmuir method. In a bipolar pulse PIII&D system, a positive and a negative pulse voltages are applied alternately to a workpiece without any other external plasma source. Simulation has been conducted for a target immersed in a very low density Ar plasma (10⁷ cm^-3) to compare the plasma generated by a negative and a positive pulse voltage applied to the target. When a negative pulse voltage is applied to the target, only a weak plasma is generated. In contrast to it, when a positive pulse voltage is applied, a two-order or more high density plasma is generated under the same condition. The plasma behavior around a trench shaped target is also presented.

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Etching characteristic LiNbO₃ and LiTaO₃ single crystals has been investigated using plasma RIE with mixture gases of CF₄/Ar, CF₄/H₂, CF₄/Ar/H₂. The etched surface was evaluated by means of atomic force microscopy and X-ray diffraction methods. The in situ surface temperature of the sample during RIE was measuresd. F atoms exist in the contamination layer, such as sediments, on the surface etched using the mixture gases of CF₄, Ar and H₂ gases. The etch rate was dependent on the orientation of a crystal. The etch rate of LiTaO₃ was less than that of LiNbO₃.

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T-shape filtered arc deposition (T-FAD) is specially designed for removing melted and un-melted macrodroplets from cathodic arc plasma and shows a superior ability to prepare droplet-free thin solid films. Furthermore, T-FAD has a feature that the film formation is done mostly by ions, since the plasma transported magnetically in T-FAD system is ionized nearly 100%. In the present study, by using T-FAD system with graphite cathode, carbon film was deposited on various rubbers. The film was verified as diamond-like carbon (DLC) by Raman spectroscopy. The DLC film was adhered well to the rubber and was not peeled off when the rubber was bended and stretched. The surface morphology, coefficient of friction, and adherence of the prepared DLC film were investigated. The surface of DLC film on rubber was not flat and has random texture structure. The coefficient of friction was lower than 0.2 in most cases. In pulling-off test (JIS K 6256) for adherence evaluation, some rubbers were broken without exfoliation of the DLC film, and the DLC films on other rubbers were peeled off at 1.3-kN/m load.

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A 3 µm thick DLC film of sufficient-adhesion was prepared on a zinc-alloy (Zn-4Al-3Cu) of low melting point (372°C) by a hybrid process of plasma-based ion implantation and deposition using hydrocarbon gases such as CH₄, C₂H₂ and C₇H₈. In this process, an RF (13.56 MHz, 3 kW) pulse for plasma generation and a negative high-voltage pulse for ion implantation were supplied to a work-piece through a single electrical feed-through. As the work-piece itself was used for RF antenna for plasma generation, the high-density pulsed plasma was produced around the work-piece. Ion implantation with the negative high-voltage pulse (-10--20 kV, 2-4 µs and 1-4 kHz) led to the reduction in compressive residual stress of DLC film and the formation of mixing layer, resulting in the thick DLC film with a 3 µm in thickness on the Zn-alloy.

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In this paper, streamer discharge in dielectric liquids which have various molecular structure, such as a double bond or a triple bond in molecular formula, is observed in detail for positive point polarity, under the application of an impulse voltage to the point electrode. As test liquids, four kinds of straight - chain hydrocarbon liquids such as n-hexane, n-heptane, n-octane and n-decane are selected and also the influence of a double bond or a triple bond included in their molecular formula on the propagation of positive streamers in these hydrocarbon liquids is investigated in detail by using a high-speed schlieren method and a current measurement system by LED, simultaneously. As a result, there are some differences in the mean propagation velocity and the propagation shape of positive streamers are seen obviously. Their shape is mainly filamentary in test liquids including a double bond or a triple bond. Also, in their liquids, positive streamer propagation are promoted. It is thought that this is due to the effect of π bond which has smaller bond energy than σ bond.

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The measurement system for a permittivity distribution has been investigated based on the measured capacitance using long distance measurement electrodes with a shield and additional electrodes. However, it has not been established to measure the permittivity distribution yet. We have compared the measured capacitance with numerical results using the experiment system with an acrylic rod. In the paper, we will discuss the capacitance variation based on the electric field deviation and verify a feasibility of the estimation method for the dielectric location using a pair of long distance parallel electrodes with additional electrodes.

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The new measurement scheme for the permittivity distribution have been proposed and tested experimentally based on the measured capacitance using a pair of long distance electrodes with the cylindrical shield and the additional arc electrodes. We have proposed the method of the electric field visualization using the electric lines of force based on the scalar potential, moreover, we have presented the new strategy in the estimation of the capacitance based on the electrostatic energy. In the paper, we will describe the capacitance of experimental results using the experiment system, where acrylic rod are inserted, and numerical results using FEM. It is found out that the capacitance is greatly influenced by the electric field deviation due to the location of dielectrics.

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We have proposed a system employing digital signal processing for real-time measurement of distance, velocity and displacement by means of optical frequency modulation in the time domain. Optical system was composed of external cavity tunable diode laser whose optical frequency was modulated into the shape of triangle wave and the unbalanced Michelson interferometer with optical path difference (as distance) between measurement arm and reference arm. Measurement arm was displaced by mounted piezo-electrical transducer (PZT). Developed signal processing instruments were named Software Instruments. The Interface circuits of input and output part expanded digital signal processor were designed and manufactured. The digital signal processor calculates the phase change of optical frequency modulation from interference signal in the time domain. The phase change is converted into the distance, the velocity and the displacements. When Software Instruments operated with sampling frequency 80kHz, this system was able to perform the measurements in the period of 1.25ms.

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This paper proposes an efficient curve fitting technique used to determine the lightning impulse parameters. The fitting curve, a modified double exponential function, is introduced to describe not only an ideal lightning impulse wave form but also a deformed one theoretically described by a triple exponential function, which is caused by a residual inductance in a generating circuit. The proposed expression is applied to measured digital record set as well as theoretically generated data. By assigning suitable weights to an objective function, precise parameter values are deduced by Levenberg-Marquardt method after small iterative calculations. The conversion formula from the modified double exponential function to a triple exponential function is also introduced with a theoretical background.

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The transient electromagnetic (EM) fields caused by an electrostatic discharge (ESD) have broadband frequency spectra, which cause serious failure to high-tech information equipment. From this perspective, an ESD testing for the EM immunity of the equipment is specified by the IEC 61000-4-2, in which the detailed waveform of the discharge current injected onto the IEC recommended Pellegrini target in contact with an ESD-gun is prescribed for calibration. However, the factors for determining the current waveform remain unclear, and thus the IEC prescribed current waveform is unlikely to be injected into actual equipment. In this study, based on the structure of an ESD-gun, an equivalent circuit modeling is proposed for analyzing the discharge current injected onto a 50-Ω SMA connector instead of the IEC target that has frequency-dependent transmission characteristics. Its validity is confirmed by comparing the calculated current waveform with the measured result. The proposed circuit modeling is also validated from measurement of the discharge current injected onto a transmission-line by the ESD-gun.

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We have improved the low-frequency axial shielding factor (ASF) of the open-ended cylindrical magnetic shield by incorporating the active canceling system to it. The amplitude and the phase of the incoming magnetic field to the shield were measured along the axis of the cylinder, and along lines on the inner and the outer surface of the cylinder in the frequency range 2 - 50 Hz. A simple feed-forward active canceling system has been developed, which consists of three canceling ring coils and a single monitoring flux-gate magnetometer. The magnetometer was located at a position on the outer surface of the magnetic cylinder, where the canceling magnetic field does not interfere to the magnetometer. The ASF achieved with active cancel was as high as 3000 at 2 Hz, 855 at 10 Hz and 113 at 50 Hz. These high ASFs can only be obtained with a longer magnetic cylinder if the active cancel is not employed.

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The authors had investigated the basic properties of newly developed stereoregular syndiotactic polypropylene (s-PP) which had been synthesized with homogeneous metallocene catalyst, in the previous paper. As the result of this, it was revealed that s-PP had superior thermal and electrical properties to cross-linked polyethylene (XLPE) which was adopted as conventional insulating material for high voltage power cable. In this paper, we estimated the possibility to apply s-PP to the actual power cable from the viewpoint of long-term thermal durability and processability. Consequently, it was found that the thermal stability of s-PP could be significantly improved by adding both hindered phenol and sulfur antioxidants, and wide molecular weight distribution of s-PP contributed to good processability during extrusion. On the basis of these results, 600V and 22kV class cables with insulation of s-PP were manufactured. Successfully manufactured cables proposed that s-PP could be available to electric power cable. Lightning Impulse and AC breakdown strength of both cables at the temperature range of RT to 120°C will be discussed.

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This paper describes a new method with singular value decomposition (SVD) for discriminating multiple sources in the brain overlapping in time. We carried out a 3-D vector measurement of somatosensory evoked field (SEF) with the electric stimulus to the right thumb, using a 3-D second-order gradiometer connected to 39-channel SQUIDs, which can detect the magnetic components perpendicular to the scalp (Br) and tangential to the scalp (B_θ, B_φ) simultaneously. The SVD method was applied to each spatio-temporal data, having two frequency ranges (1-40Hz, 15-40Hz), with the time window of 25ms and it was shifted every 2.5ms in analysis. Two dominant singular values were obtained for each of three components, respectively. It was found that magnetic field distribution with 15-40Hz was different to that of 1-40Hz at around 92ms latency corresponding to the SII activity overlapped in the SI activity. It was also confirmed a good agreement between isofield contour maps of measured magnetic field and theoretical maps calculated by signal subspaces with SVD analysis. We conclude this proposed method using dynamic SVD method with different frequency ranges is useful for discriminating multiple sources overlapping in time.

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The melt-spun ribbons of Pr-Fe-Co-W-B system alloys were prepared by single roller rapid-quenching method. The effects of composition, wheel velocity and heat-treatment on the magnetic properties were investigated. The Pr₉Fe_76.7Co₈W_0.3B₆ ribbon prepared at a wheel velocity of 15.0 m/s were crystallized by heat-treatment, and the optimum heat-treatment condition was found to be at 600 °C for 3 min, then the value of (BH)_max was 148.5 kJ/m³. The temperature coefficients of J_r and H_cJ for the ribbons crystallized from the amorphous Pr₉Fe_76.7Co₈W_0.3B₆ alloy were α(J_r)=-0.03 %/°C(reversible)and α(H_cJ)=-0.45 %/°C(irreversible), respectively. The value of (BH)max for the compression molding Pr₉Fe_76.7Co₈W_0.3B₆ isotropic bonded magnet prepared by using the ribbons annealed at 600 °C for 3 min is 86.00 kJ/m³ and the density is 6.16 Mg/m³.

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In this study, an artificial void model was made on the basis of the Whitehead abc model and time to breakdown of a PP film which formed the artificial void was investigated with the Weibull distribution. Voltage dependence of time to breakdown of the PP film (V-t characteristic) becomes discontinuous at a certain voltage between 12 and 13kV. Furthermore, repetition of the breakdown mechanism transition (fatigue-failure- type→ random-failure-type or early/random-failure- type) occurs at the certain voltage. These results suggest that patterns of surface discharge in the artificial void change from Polbüschel to Gleitbüschel.

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