Proton beam writing (PBW) is a direct writing technique for the fabrication of micro- and submicron-scale structures with high-aspect ratio. The straight trajectory of MeV protons incident to target materials allows high-aspect-ratio micromachining with high throughput, when compared with a conventional direct writing process using low-energy electron beam. The principles and superior features of the PBW technique are illustrated by demonstrating the micromachining by PBW on various resists. Application of the high-aspect-pillar structures by PBW is also demonstrated for electro-micro filters using dielectrophoresis.

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The interfaces, organic semiconductor/gate insulator and organic semiconductor/ source-drain (S-D) electrodes, in organic thin-film transistors (TFTs) are crucial for the improvement of transistor characteristics. We describe (1) the improvement of mobility and lowering driving voltage by treating the gate-insulator surface with self-assembled monolayers, and (2) the reduction of contact resistance by employing a carrier injection layer for the S-D electrodes in bottom-contact organic TFT.

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In this study, we focus on deterioration in the shield property caused by penetrating a power wire through a transfixion hole. The shield structure of circular transfixion hole filled the space between the cable and the penetration part with dielectric and magnetic loss material is proposed, and shield property is evaluated by FDTD method and measuerment. As a result, it is confirmed that shield property decreases in case of penetrating a power wire through a circular transfixion hole compared with that of only circular hole, because this structure becomes circular coaxial line. Moreover, dielectric and magnetic loss material is filled in the space between the cable and the penetration part, it is clarified that shield property is improved about 20dB. Therefore, the effectiveness of this proposed structure to real transfixion hole can be confirmed quantitatively.

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The rotation angle of polarization plane of propagating beam was experimentally measured using a polarization controlled laser beam, repeating square mirror, and discharge apparatus. A rotation angle of 0.29 degrees was obtained in the case of discharge gap of 4 cm and charge voltage of 50 kV. The result was in good agreement with the simulation of the experimental model. The waveform of the rotation angle showed a similar time dependence as the discharge current, with a correlation coefficient of>0.94.

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We describe about characteristics of creeping discharge developed in a narrow gap with a backside electrode, under μs pulse voltage application. As a result, in the gas with 3% SF₆ mixture in N₂, the flashover voltage in the pressures of 0.2 and 0.3MPa decreased by approximately 5% compared to that of 0.1MPa in both a filamentous straight backside electrode and a filamentous curve backside electrode. V-characteristics of which flashover voltage decreased were obtained by SF₆ mixture in N₂. We obtained V-characteristics on the flashover voltage at SF₆ content in the range of D=3%-100% for a filamentous backside electrode. Flashover voltages at a filamentous straight backside electrode were higher than that of a filamentous curve backside electrode. From the corona observation using ultra-high speed camera, it was found that the flashover is generated along the backside electrode.

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Electrical conduction and complex permittivity are examined in polyethylene terephthalate succinate, focusing on their relations to dielectric relaxation processes. Both the real and imaginary parts of complex permittivity, namely dielectric constant ε_r' and dielectric loss factor ε_r'', increase with a decrease in frequency, especially at high temperatures. They are both ascribed to the transport of ionic mobile carriers. Namely, the carrier transport forms conduction current that should contribute to ε_r''. On this occasion, if charge exchange does not occur at the two electrodes, heterocharge layers should be formed before the electrodes. This should increase the charge density on the electrodes, thus contributing to ε_r'. In addition to the increase in ε_r' and ε_r'' due to mobile ions, two relaxation processes, one due to micro-Brownian motion of dipoles and the other due to orientation and magnitude change of the dipole moment induced by two end groups in the polymer main chain, are observed. Corresponding to these two relaxation processes, two thermally stimulated discharge current (TSDC) peaks appear. The two TSDC peaks as well as the increment in ε_r' and ε_r'' become larger when the crystallinity of the sample decreases.

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This paper reports the high power characteristics of a pyramidal absorber produced by the traditional roof tile smoking technique. In the production process, the pyramid is sintered at about 1000°C that leads to the strong resistance against the temperature rising due to the high power microwave absorption.

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A new multipoint Thomson Scattering measurement system has been developed using multiple refrections and time-of-flight of laser light. The new idea of our system is to utilize the time delay of the scattered light of the multiplly reflected laser beam as a means to save the numbers of spectrometers and detectors. They enabled us to measure one dimensional profile of electron temperature and density by a single polychromator, proving its basic principle.

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