The analysis of the breakdown characteristics in KrF excimer gas with a charge transfer circuit is made. We calculate the breakdown characteristics assuming a zero-dimensional uniform plasma in the prebreakdown region. And we measured them in the range of 0.3-6.0% Kr, 0.1-0.25% F₂ and 0.24-0.36MPa total pressure.
The measured and calculated breakdown characteristics are in a good agreement, then we explain principal factors controlling the breakdown. The results are as follows, (1) the electron multiplication process in the prebreakdown region is mainly controlled by the direct ionization of Kr and dissociative attachment of F₂, (2) the breakdown voltage has a minimum value with the variation of Kr partial pressure, and this characteristic corresponds to the variation of the ionization collision frequency, (3) the breakdown voltage increases with F₂ partial pressure, and this is caused by the reduction of the electron multiplication due to the dissociative attachment, (4) the breakdown voltage increases with the total pressure, and this is caused by the reduction of the electron multiplication due to the decrease of the reduced electric field E/N.

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Voltage generated in MIM structures of Langmuir-Blodgett(LB) heterofilms was measured at temperatures 28.5°C, 43.6°C and 60.0°C. Structures of MIM samples are as follows,
Al/C₂₀/TCNQ/C₂₀/Al
In above structures, C₂₀ indicate arachidic acid LB films and TCNQ is 2-pentadecyl-7, 7', 8, 8'-TCNQ LB film. Voltage generated in the present MIM samples decreased with temperature rise. Investigating the phenomenon mentioned above, temperatrure dependences of diffusion constant D of electrons in LB heterofilms and conductance α of LB heterofilms are measured, and voltage generation was analyzed by D and α. As a result, temperature characteristics of generated voltage is due to temperature dependences of diffusion of electrons in LB heterofilms and conductance of LB heterofilms. In this case, it is considered that voltage generation is due to diffusion current by electrons and conduction current in LB heterofilms.

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In the present paper, MIM structures of LB heterofilms based on LB Heterofilms of arachidic acid LB films (C₂₀) and 2-pentadecyl-6, 7', 8, 8'-TCNQ LB films (TCNQ) were deposited on the slide glass of microscope as follows.
Al/C₂₀(4L)/TCNQ(4L)/C₂₀(4L)/Al
Here, 4L indicates the number of monolayers, namely 4 monolayers.
It has been well known that voltage is generated in such a MIM structures, and voltage generation seems to be due to chemical reaction in LB films. However, it is suggested in our investigation that the cause of voltage generation is diffusion of electrons in LB films.
In the pressent paper, it is shown that the series and parallel connection cheracteristics of the present MIM structures can be explained by the equivalent circuit of the MIM expressed by current source and resistance.

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A polymer dielectric material tends to be easily charged, and may cause an electrostatic discharge which becomes a serious problem because the consequent electromagnetic noise damages electronic circuits in various kinds of apparatus. In order to prevent an electrostatic discharge, the new materials have been developed. The anti-electrostatic polymer includes some kinds of polymer solid-electrolytes, so that space charge originally exists inside the materials. We investigate the mechanism of the anti-electrostatic discharge effect of the polymer by measuring the space charge distribution using the high resolution pulsed-electroacoustic method. The experimental results suggest that the internal space charge of the polymer accumulates at the surface, and forms the hetero charge distribution at the interface between the electrodes and the specimen. Thus, internal space charge compensates the applied electric field, resulting in preventing the increase of the surface potential. In addition, internal space charge behavior relates to the the dispersion condition of the polymer solid-electrolyte that depends on the quantity of the electrolytes and the procedure of the specimen.

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Glass-silicon anodic bonding has been used for the fabrication of silicon micro sensors. A structural distortion during the anodic bonding process is sometimes observed and leads to the difficulty in fabricating the sensors with narrow gaps. It is considered that the distortion is mainly caused by not only the deference of thermal expansion coefficient between glass and silicon but also the structural change with the movement of ions in glass plate.
This paper describes the experimental results which shows the effects of the bonding temperature and the movement of the positive ion in glass plate. It is also demonstrated that the structural distortion can be reduced by using a thick glass plate having high rigidity.

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We simulated emission currents and electron beam trajectories from a micron size field emitter which consists of an emitter electrode and a gate electrode using the electron gun analysis program EGN2. The parameters such as a height, a half angle and a curvature radius of an emitter electrode influence the emission current significantly. The results of our calculations suggest that the largest emission current occurs when the emitter electrode is as high as the upper surface of the gate electrode and the smaller the half angle is, the larger emission current we have. We also carried out simulations of an electron beam from a field emitter with a focus electrode to reduce a divergence angle of an electron beam. Taking into consideration the existence of a bump at the tip of the emitter electrode, there is a good agreement between calculated and experimental results of the emission current vs. the focus electrode voltage charac- teristics.

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In order to realize light and small power supplies, we propose here a film shape transformer named the film transformer. The basic operating principle of this transformer is the skin effect similar to those of the coreless transformer which is exploited previously by us. Both the primary and secondary coils composed of thin film conductors are arranged coaxially on one layer film base, and the film transformer is constructed by the lamination of these films.
In this paper, experimental as well as numerical studies are carried out about basic characteristics of the film transformer in order to examine possiblities in practical use. As a result, it is revealed that the film transformer may be applicable to the high frequency swiching power supplies.

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A system for nondestructive measurement is developed using SQUID (Superconducting Quantum Interference Device) gradiometer. The system is composed of a DC-SQUID gradiometer integrated with a pickup coil, a cryostat with thin vacuum space (liquid helium container), a non-magnetic stage for sample and a computer. The pickup coil of SQUID is a coplanar concentric second order gradiometer to remove environmental and background magnetic noises, and to raise spatial resolution. The stage is driven by air pressure using a rod-less-cylinder. The thickness of the bottom of cryostat is 2.5 mm. The magnetic field radiated from a small coil (2mm in diameter and 200 turns) was measured by this system. The results agreed well with calculation results.

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The Behavior of electrons produced by UV preionization is investigated in mixtures of helium/krypton and helium/fluorine. The concentration of krypton and fluorine is varied in the range of 1 to 20% and 0.05 to 0.3%, respectively. Excimer laser output is obtained for He/Kr/F₂=97.8/2/0.2%. In the mixtures of helium/krypton, electron density decreases with the increase of krypton concentration, because the DV light is absorbed by the krypton in a space between UV source and electron detection electrodes. After few microseconds from the initiation of an arc discharge for the preionization, the number of electrons decreases owing to the absorption of UV photons with the krypton and the electron attachment by the fluorine. It is found in the case of helium/fluorine gas mixtures that the preionized electron density is inversely proportional to the fluorine concentration owing to the attachment. For the laser gas mixtures, the electron density becomes lower by a rate of one-tenth of that of helium/krypton and helium/fluorine mixtures. The lower electron density is caused by the UV absorption by the krypton and the attachment. It is discussed that the increase of the electron density brings a larger laser energy due to the production of a stable pumping discharge for the laser.

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The condition of saturated superfluid helium produces easily the discharge environment near the Paschen minimum condition of gaseous helium. It is very important from a point of magnet protection to know surface breakdown voltage in that condition. We measured breakdown voltage of surface or gap discharge in gaseous helium the condition of which is some higher regime than saturation temperature for various pressures (1.33 to 101kPa), using parallel plane electrodes with a tested spacer. In the tested regime, the breakdown voltage obeys Paschen's law and changes only with the density-thickness product. In lower density-thickness product range, surface discharge can hardly occur before the gap dischage develops, and breakdown voltage is the same as that of the same spacing gap dischage without the spacer. In higher density-thickness product range, surface breakdown voltage is lower than the gap breakdown voltage. Within the scatter of the data, breakdown voltage is independent of spacer diameter and thickness.

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With an objective to study the final dielectric breakdown process by which a water tree converts into an electrical tree, characterized (density, impurity and water content, water tree density, oxidation) crosslinked polyethylene (XLPE) samples taken from two 28kV field-aged cables were aged at 10kV/mm, 60Hz electric stress in the presence of 0.05 or 1M NaCl electrolyte at 22-23°C. The results indicate that water tree growth saturated as a function of test time and was only slightly. influenced by NaCI concentration. Also it was found that the length of laboratory grown water trees was not affected by the presence of field grown water trees. The AC breakdown (ACBD) strength was influenced to a certain extent by the length of laboratory grown water trees. The aging conditions have led to the growth of non-conductive water trees which have almost no electric field enhancement at their tips and subsequently with no possibility to generate pre-breakdowns or electrical trees. Other mechanisms such as surge or lightning impulses, or partial discharges at operating voltage must be considered in order to effect the conversion of water trees to electrical trees.

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We discussed the electrical properties (carrier injection and carrier transport) of the organic electroluminescent diodes (ELD) with triphenyl diamine derivative (hole transport layer) and aluminum quinoline (emission layer). The apparent activation energy of current in organic ELD was estimated to be 0.12eV from Arrhenius plot. As it was consistent with the activation energy of hole mobility of TPD, we suggested that the carrier transport in organic ELD is closely related to hole transport of hole transport material. The introduction of TPD layer between Alq3 and cathode suppressed the current density and the EL efficiency per current density. The EL efficiency of organic ELD was thought to depend upon the electron injection from cathode into emission layer. We estimated the trap depth and the trap density of Alq3 thin film using the thermally stimulated current method and the space charge limited current model for the first time. They are estimated to be about 0.8eV and 1017cm-3, respectively. We showed from the discussion of energy diagram that the trap center act as an carrier trap, but not as an recombination center.

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Baron nitride films were deposited on Si (100) substrates by using a pulsed YAG laser to ablate hBN and cBN-Co alloy targets. The composition of the BN film depends on the nitrogen gas pressure. Auger Electron Spectroscopy shows that the stoichiometric BN films are obtained under the conditions; a laser fluence of 3.8 J/cm², the substrate temperature of 650°C and nitrogen gas pressure of 10.0 Pa. Addition of argon gas to the reactant nitrogen gas and an RF bias enhances the formation of the cubic BN phase. Fourier Transform IR reflection spectroscopy shows that argon ion bombardment by the RF bias is effective for the formation of cBN films. This is the first report that the cubic BN phase is formed by the pulsed YAG laser deposition with an RF bias. Optical emission measurement of the hBN plasma plume indicates the presence of N₂ and B, with no strong evidence of molecular BN emission. The hBN target in this process seemed to be mainly ablated as an atomic state.

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To develop a sodium immersed type electromagnetic pump which is expected to contribute to the realization of the FBR plant in the near future, the establishment of an electrical insulating technique at temperatures exceeding 500°C is indispensable. Also, the mechanism of the dielectric deterioration has to be understood.
Using mica-alumina combined insulation, an ageing test was performed by applying high voltage in nitrogen at high temperatures. As a result, all the specimens with high voltage applied at 750°C caused dielectric breakdown around 1000 hours, but an emergency signal could be detected before dielectric breakdown by monitoring the a. c. current. Mica splittings insulation is superior in dielectric performance to mica paper. The deterioration mechanism was found to be mainly subject to thermal influence.

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The single crystals of Ba_1-xK_xBiO_y (BKBO) with wide potassium composition range (x=0-0.6) were synthesized by electrochemical method. As grown crystal shows high superconducting transition temperature (-30K) and narrow transition width without oxygen annealing. The quantitative chemical analyses were performed for those crystals by EPMA, TGA and iodometry. Though oxygen content of as grown crystals decreases with potassium content increases, Oxygen deficiency is as low as 0.05. The crystals grown electrochemically is considered to be in high oxidation state. It is revealed that both potassium and oxygen play a key role in the superconductivity of BKBO.

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The effect of atmospheric pressure on tracking resistance of organic insulating materials were investigated in the range of 500 to 1007 hPa. The tracking resistance for Polycarbonate (PC), Modified Polyphenylene Oxide (M-PPO) and Paper Base Phenolic Resin Laminate (PL) increase with the decrease in atmospheric pressure. The scintillating discharges on these samples surface lead to the ignition. The tracking failure on these results from the ignition on the surface. For Polybutylene Terephthalate (PBT) and Polyethylene Terephthalate (PET), the tracking resistance decrease with the decrease in atmospheric pressure. The discharges observed on the these surface are the glow-like. The discharge area spreads on the surface between the electrodes at the lower pressure. The failure on this group results from the carbonization by the discharges on the surface. However, the tracking resistance for Unsaturated Polyester Resins (UP) has no significant dependence on lower atmospheric pressure.

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PMMA films with dye additive were prepared by the solution-grown casting method. Three kinds of dye were used: p-aminoazobenzene (Ab), p-nitorobenzeneazo-resorcinol (Nb) and Methyl-yellow (My). The film, 100μm thick, was set on PMMA board of 3mm thick. The film with the board was sandwiched between a sphere electrode of 50Hz HV and a plane electrode connected to the ground potential.
In the case of the film with Ab additive at 0.05 wt%, the number and total charge quantity of the PD pulses were reduced to about 50% less than those in the case of the film without additive. The reduction of ac PDs on the Ab film was effective under an electric field strength little higher than the ac partial discharge's inception. In the cases of the films with the other dyes, the reduction of ac PD was un- observed.
The reduction of ac PD on the Ab film was explained by using the results of the surface voltage distribution on the film measured at zero-crosses of ac voltage applied. It was considered that ionization of the electron donor type of dye (Ab) in the film plays an important role on the surface voltage distribution on the film where ac PD generates.

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