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991.
G. X. Liu F. K. Shan J. J. Park W. J. Lee G. H. Lee I. S. Kim B. C. Shin S. G. Yoon 《Journal of Electroceramics》2006,17(2-4):145-149
Ga2O3 and Ga2O3-TiO2 (GTO) nano-mixed thin films were prepared by plasma enhanced atomic layer deposition with an alternating supply of reactant
sources, [(CH3)2GaNH2]3, Ti(N(CH3)2)4 and oxygen plasma. The uniform and smooth Ga2O3 and GTO thin films were successfully deposited. Excellent step coverage of these films was obtained by chemisorbed chemical
reactions with oxygen plasma on the surface. The dielectric constant of GTO thin film definitely increased compared to Ga2O3 film, and the leakage currents of GTO films were comparable to Ga2O3 films. The leakage current density of a 40-nm-GTO film annealed at 600∘C was approximately 1×10−7 A/cm2 up to about 600 kV/cm. 相似文献
992.
Shin‐Ichi Tanaka Tsukasa Miyagi Toshiya Ohtaka Mikimasa Iwata Tadashi Amakawa Yutaka Goda 《Electrical Engineering in Japan》2011,174(4):9-18
This paper describes the phenomenon of internal pressure‐rise due to arcs ignited between metal rod electrodes in air. First, the internal pressure‐rises in a closed chamber due to arcs were measured at currents within the range of 1 to 12.5 kA. The rod electrodes were made of copper, iron, and aluminum, and were 20 mm in diameter. The measurements showed that the maximum pressure‐rise distinctly differed with each electrode material at the same total arc energy, namely, the maximum pressure‐rise was the highest in the case of the aluminum electrode and was the lowest in the case of the iron electrode. Next, to quantitatively verify this difference, the internal pressure‐rise was estimated, taking into account the energy balance in the closed chamber on each electrode material. It was found that the estimated pressure‐rise approximately agreed with the above experimental results by taking into consideration oxidation reactions of the electrodes, melting and vaporization of the electrodes, and radiation loss of the arcs under certain realistic assumptions. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(4): 9–18, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21071 相似文献
993.
Ploss B. Shin F.G. Chan H.L.W. Choy C.L. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2000,7(4):517-522
This paper studies the pyroelectric coefficient of 0-3 composites consisting of 27%vol lead titanate (PT) powder embedded in a vinylidene fluoride-trifluoroethylene copolymer (PVDF-TRFE) matrix. The constituent phases of the composites have been polarized in four possible ways: only the copolymer polarized; only the ceramic polarized; the copolymer and ceramic phases polarized in the same direction; the two phases polarized in opposite directions. The pyroelectric coefficient was measured by a dynamic method at 5 mHz within the temperature range 20 to 90°C (which covers the ferroelectric to paraelectric phase transition temperature of the copolymer matrix). The composite with the copolymer and ceramic phases polarized in the same direction exhibits strong pyroelectric but relatively weak piezoelectric activity, and vice versa when the constituent phases are oppositely polarized. A theoretical model is used to analyze the pyroelectric coefficient of the composites in terms of the pyroelectric and dielectric properties of the copolymer matrix as determined from experiment, and those of the ceramic particles which are assumed to be temperature independent. The pyroelectric coefficient and dielectric permittivity of the ceramic particles are obtained as fitting parameters. The theoretical prediction is found to agree well with the experimental data 相似文献
994.
Won-Jae Lee Guoxia Liu Byoung-Chul Shin Geun-Hyoung Lee Il-Soo Kim Nam-Yeal Lee Sang-Ouk Ryu Woong-Chul Shin Jae-Man Lee Jindong Kim 《Journal of Electroceramics》2004,13(1-3):71-75
The phase formation and electrical properties of (Bi, La)4Ti3O12 (BLT) thin film and V-, Sm-doped BLT thin films prepared by the chemical solution deposition method on Pt/TiO2/SiO2/Si substrates have been investigated. It was observed that the microstructure and electrical properties of BLT thin films dramatically varied with V- and Sm-doping. The crystallinity and grain size of BLT thin films were definitely increased by V- and Sm-doping into BLT films, which resulted in the enhancement of remanent polarization in doped BLT films. The remanent polarization (Pr) of Sm-doped BLT films annealed for 3 min by an RTA system was about 9 C/cm2. The V- and Sm-doped BLT films also exhibited good fatigue characteristics under bipolar stressing to 1010 cycles. 相似文献
995.
Aging and Annealing Effects of ZnO Thin Films on GaAs Substrates Deposited by Pulsed Laser Deposition 总被引:2,自引:0,他引:2
F. K. Shan Z. F. Liu G. X. Liu W. J. Lee G. H. Lee I. S. Kim B. C. Shin Y. S. Yu 《Journal of Electroceramics》2004,13(1-3):195-200
Zinc oxide (ZnO) thin films were deposited on GaAs (100) substrates at different temperatures in the pulsed laser deposition (PLD) system. From the measurements of X-ray diffraction (XRD) at room temperature, 300–500°C were found to be good condition for the crystallization of the thin films. From the photoluminescence (PL) measurements, 500°C was found to be the optimized temperature for its optical property. Samples grown at 100, 200, 300, and 400°C showed near band-edge (NBE) emissions and deep-level emissions. The intensity of deep-level emissions decreased as time goes on, which is believed to originate from oxygen vacancies or zinc interstitials in thin films. While for the sample grown at 500°C, bright NBE emissions were observed at room temperature, and no deep-level emissions observed. This means that the high-optical-quality thin film was grown at 500°C. At the same time, annealing process of ZnO thin films grown at room temperature was carried out in PLD chamber. It was found that the annealing temperature of 600°C has strong effects on its PL. Aging and annealing effects in ZnO thin films grown on GaAs substrates by PLD were observed for the first time. 相似文献
996.
We have developed a robust vision system for 2D positioning of industrial parts stable to changes of lighting conditions. A wide dynamic range vision sensor that we had developed previously was used to avoid the saturation of object images. Additionally, a gray scale pattern matching technique was employed for robust image processing. Performance of the system with a wide dynamic range vision sensor was investigated experimentally in comparison with that of a system with a conventional video camera. The probability of correct positioning of an object under changing lighting conditions, simulating those in a factory, was 100% for the wide dynamic range vision sensor and 83% for the conventional video camera. The experimental results confirm the effectiveness of the developed system, revealing that dynamic range expansion of the video cameras is very effective for realizing robust robot vision systems. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(2): 34–40, 1997 相似文献
997.
Wooyoung Kim Pil Kim Ji Bong Joo Hyun Khil Shin Kwang S. Jung Jongheop Yi 《Journal of Electroceramics》2006,17(2-4):679-682
Porous carbon materials with a cylindrical pore structure were prepared using ordered mesoporous silica as a removable template.
To investigate the effect of the structural and textural properties of the products on hydrogen adsorption capacity, different
carbon precursors and synthetic methods were used in their preparation. All of the carbon materials prepared showed a well-defined
pore structure with a high surface area irrespective of the carbon precursor used in the preparation. Hydrogen adsorption
tests indicated that the capacity of the materials for hydrogen adsorption was highly dependent on total surface area and
the pore structure. Based on the N2 sorption results, the total surface area was directly correlated with the hydrogen adsorption capacity. 相似文献
998.
Sin‐Woo Lee Hyun‐Lark Do 《International Journal of Circuit Theory and Applications》2016,44(7):1455-1467
An efficient bridgeless power factor correction converter with reduced voltage stress is proposed. In the proposed converter, the input full‐bridge rectifier is removed to reduce the conduction loss of rectification, and the voltage stress of switching devices is significantly reduced by utilizing the additional circuit composed of a capacitor and a diode. Therefore, low‐voltage‐rating diodes with less forward voltage drop and low‐voltage‐rating Metal‐Oxide‐Semiconductor Field‐Effect Transistor (MOSFET) with low RDS(on) is utilized. The proposed converter is based on the single‐ended primary‐inductor converter power factor correction operation in discontinuous conduction mode to achieve a high power factor with a simple control circuit. Consequently, the proposed converter can provide a high power factor and a high power efficiency, and it is also suitable for low‐cost converter for high input/output voltage system. The operational principles, steady‐state analysis, and design equations of the proposed converter are described in detail. Experimental results are verified for a 130 W prototype at a constant switching frequency 100 kHz. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
Woo-Chang Choi Zhixin Wan Ji-Hoon Ahn Doo-In Kim Seung-Yong Shin Kyung-Il Moon Jin-Seong Park Jung-Dae Kwon Se-Hun Kwon 《Journal of Electroceramics》2014,32(2-3):240-245
Ru-AlN thin films were suggested as a novel multifunctional heating resistor film for non-passivated type thermal inkjet printer devices. Ru-AlN thin films were prepared by plasma-enhanced atomic layer deposition in order to intermix Ru and AlN precisely. When the Ru intermixing ratios were optimized, Ru-AlN films showed a favorable electrical resistivity (from 490.9 to 75.3 μΩcm) and minimized temperature coefficient of resistance (TCR) values (from 335 to 360 ppm/K). Moreover, the Ru-AlN films showed a strong oxidation resistant as compared with commercially used TaN0.8 films because the prepared Ru-AlN thin films had a typical nanocomposite structure. By applying electrical pulses to the heater device using Ru-AlN thin films for a Joule heating, a reliable operation was also proven. 相似文献
1000.