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91.
ZAO透明导电薄膜的制备及性质 总被引:1,自引:0,他引:1
ZAO(ZnO:Al)透明导电薄膜是一种具有高的载离子浓度和宽禁带的半导体氧化物,电学和光学性能优异。极具应用前景。本文介绍了ZAO薄膜的制备现状、特性、磁控溅射参数对其电学和光学性质的影响以及今后研究的方向。 相似文献
92.
We have fabricated, by simultaneous DC and RF magnetron sputtering, multilayer transparent electrodes having much lower electrical resistance than the widely used transparent conductive oxide electrodes. The multilayer structure consists of three layers (ZnO/Ag/ZnO). Ag films with different film thickness were used as metallic layers. Optimum thicknesses of Ag and ZnO films were determined for high optical transmittance and good electrical conductivity. Several analytical tools such as spectrophotometer, atomic force microscopy, scanning electron microscopy and four-point probe were used to explore the possible changes in electrical and optical properties. A high quality transparent electrode, having resistance as low as 3 Ω/sq and high optical transmittance of 90% was obtained at room temperature and could be reproduced by controlling the preparation process parameters. The electrical and optical properties of ZnO/Ag/ZnO multilayers were determined mainly by the Ag film properties. The performance of the multilayers as transparent conducting materials was also compared using a figure of merit. 相似文献
93.
94.
In this paper, electrical characteristics of metal-oxide-semiconductor field effect transistor (MOSFET) with silicon/gallium-arsenic
(Si/GaAs) stacked film are numerically studied. By calculating several important device characteristics, such as the on-state
current, the subthreshold swing, the drain induced barrier lowering, the threshold voltage, the threshold voltage roll-off,
and the output resistance, a 50 nm Si/GaAs MOSFET is simulated with respect to different thicknesses of Si/GaAs film. Compared
with the results of pure Si MOSFET, Si/GaAs MOSFET shows promising characteristics after properly selecting the thickness
of Si/GaAs film. Among Si, germanium (Ge), and Si/Ge MOSFETs, Si/GaAs MOSFET relatively exhibits a higher driving capability
due to higher carrier mobility within the Si/GaAs film. However, quantitatively accurate estimation of device characteristics
will depend upon more precise calculation of band structure of the stacked film. 相似文献
95.
针对智能化电气设备的工作特点,设计了有针对性的专业实时操作系统(S-RTOS)。它的调度内核的正确性已被证明(实际应用)。 相似文献
96.
刘红 《广东输电与变电技术》2005,(1):20-21
变压器对抗短路强度的要求是很高的。文中介绍了变压器短路时的电动力的作用情况,结合单位实际情况介绍了提高变压器抗短路能力的措施。 相似文献
97.
98.
99.
B. Ouertani J. Ouerfelli M. Saadoun B. Bessaïs H. Ezzaouia J.C. Bernde 《Materials Characterization》2005,54(4-5):431-437
FeS2-thin films with good crystallinity were synthesized by a simple method which consists of sulphuration, under vacuum, of amorphous iron oxide thin films pre-deposited by spray pyrolysis of FeCl3·6H2O (0.03 M)-based aqueous solution onto glass substrates heated at 350 °C. At optimum sulphuration temperature (450 °C) and duration (6 h), black green layers having granular structure and high absorption coefficient (5.104 cm−1) were obtained. The study of the electrical properties of the as-prepared films vs. the temperature variations showed three temperature domain dependence of the conductivity behaviour. The first one corresponds to the high temperature range (330 K–550 K) for which an Arrhenius plot type was obtained. The activation energy value was estimated at about 61.47 meV. The second domain corresponding to the intermediate temperature range (80 K–330 K) showed a variable activation energy between the grain boundaries. The barrier height, q¯, was estimated to 27±0.5 meV, and the standard deviation, qσ, was evaluated at about 14±0.5 meV. We found that at lower temperatures (20 K–80 K), the conductivity is governed by two conduction types. The density of localised states, was about 2.45×1020 eV−1 cm−3. 相似文献
100.
J.M. Peza-Tapia V.M. Snchez-Resndiz M.L. Albor-Aguilera J.J. Cayente-Romero L.R. De Len-Gutirrez M. Ortega-Lpez 《Thin solid films》2005,490(2):142-145
The structural, electrical and optical properties of Na-doped CuInS2 thin films grown by spray pyrolysis were studied. These films crystallized in the sphalerite structure of CuInS2, and showed to contain traces of indium sulfide and CuIn5S8 as impurity phases. All films were In-rich and showed p-type conductivity. The film conductivity was strongly affected by Na-doping, which decreased from 10−2 to 10−5 S/cm by increasing the [Na]/[Cu] ratio from 0.005 to 0.03 in the spray solution. The band gap energy was observed to increase, from 1.4 to 1.45 eV, with increasing the [Na]/[Cu] ratio. Our results suggested that Na could be an effective acceptor impurity in sprayed CuInS2. 相似文献