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51.
《Microelectronics Journal》2014,45(12):1612-1620
Organic materials can be used to fabricate sensors for physical and chemical quantities, and also to make electronics. The integration of these two elements holds the promise to enable novel smart-sensors on foil. In this paper, we deal with the design of the first stage of a signal conditioning chain on foil: the amplifier. The poor electrical performance of organic TFTs hampers the design of complex circuits, and negatively affects the characteristics of continuous-time amplifiers. In order to improve small-signal gain and speed, a mixed discrete-time and continuous-time approach is presented in this paper for the sensor frontend. A new device, the Thin-Film Trans-Capacitor, is presented and used to build the discrete-time amplifier, while the continuous time amplifier exploits a simple traditional architecture to improve yield. Simulations of the circuit proposed show that the total gain of the sensor frontend increases of about one decade without any detrimental effect on the speed. CAD (Computer-Aided Design) simulations confirm the results of the simple mathematical model we present. 相似文献
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针对三维芯片中硅通孔(through-silicon via, TSV)的准确电学建模问题,本文提出了一种电阻电容(RC)电路模型以及相应的有效参数提取技术。该电路模型同时考虑了半导体效应与静电场影响,适合于低频与中频的电路信号范围。该方法采用一种基于悬浮随机行走(floating random walk, FRW)算法的静电场电容提取技术,然后将它与刻画半导体效应的MOS电容结合,形成等效电路模型。与Synopsys公司软件Sdevice所采用的对静电场/半导体效应进行完整仿真的方法相比,本文方法计算效率更高,并且也能处理一般的TSV电路版图。对多个含TSV的结构进行了计算实验,结果验证了本文方法在从10KHz到1GHz频率范围内的建模准确性,也显示出它相比Sdevice方法最多有47倍的加速比。 相似文献
54.
We have investigated the temperature dependent interfacial and electrical characteristics of p-GaAs metal-oxide-semiconductor capacitors during atomic layer deposition(ALD) and annealing of HfO2 using the tetrakis(ethylmethyl) amino hafnium precursor. The leakage current decreases with the increase of the ALD temperature and the lowest current is obtained at 300℃ as a result of the Frenkel-Poole conduction induced leakage current being greatly weakened by the reduction of interfacial oxides at the higher temperature. Post deposition annealing(PDA) at 500℃ after ALD at 300℃ leads to the lowest leakage current compared with other annealing temperatures. A pronounced reduction in As oxides during PDA at 500℃ has been observed using X-ray photoelectron spectroscopy at the interface resulting in a proportional increase in Ga2O3. The increment of Ga2O3 after PDA depends on the amount of residual As oxides after ALD. Thus, the ALD temperature plays an important role in determining the high-k/GaAs interface condition. Meanwhile, an optimum PDA temperature is essential for obtaining good dielectric properties. 相似文献
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以电化学石英晶体微天平(EQCM)为主要测试手段,在不同浓度的高氯酸钠(NaClO4)水溶液中研究了水合离子吸附到活性炭电极孔隙过程中电极的质量变化.对于每种电解液,根据Raman光谱和EQCM数据分别计算了本体溶液中和电极/溶液界面上Na+的水合数.通过比对这两组Na+水合数,探讨了Na+存储到活性炭负极过程中的去溶剂化效应. 相似文献
58.
《Current Applied Physics》2015,15(11):1384-1388
Thin-film multi-layer ceramic capacitors (MLCCs) were prepared using high-dielectric constant Bi2Mg2/3Nb4/3O7 thin-films deposited at room temperature via radio-frequency magnetron sputtering. The multi-layer capacitors, in sizes 0402, 0603 and 1005, were well equipped with both inner and outer Cu electrodes. The capacitances of the bi-layer capacitors were twice that of the single-layer version in sizes 0402, 0603, and 1005. The 200 nm-thick Bi2Mg2/3Nb4/3O7 thin-films would be suitable for thin-film multi-layer capacitor applications. 相似文献
59.
Hongyun Ma Hongwu Chen Mingmao Wu Fengyao Chi Feng Liu Jiaxin Bai Huhu Cheng Chun Li Liangti Qu 《Angewandte Chemie (International ed. in English)》2020,59(34):14541-14549
Capacitive energy storage has advantages of high power density, long lifespan, and good safety, but is restricted by low energy density. Inspired by the charge storage mechanism of batteries, a spatial charge density (SCD) maximization strategy is developed to compensate this shortage by densely and neatly packing ionic charges in capacitive materials. A record high SCD (ca. 550 C cm?3) was achieved by balancing the valance and size of charge‐carrier ions and matching the ion sizes with the pore structure of electrode materials, nearly five times higher than those of conventional ones (ca. 120 C cm?3). The maximization of SCD was confirmed by Monte Carlo calculations, molecular dynamics simulations, and in situ electrochemical Raman spectroscopy. A full‐cell supercapacitor was further constructed; it delivers an ultrahigh energy density of 165 Wh L?1 at a power density of 150 WL?1 and retains 120 Wh L?1 even at 36 kW L?1, opening a pathway towards high‐energy‐density capacitive energy storage. 相似文献
60.
适用于高电压测试的电容器分选机 总被引:1,自引:0,他引:1
靳建鼎 《电子工业专用设备》2006,35(4):39-42
分选是电容器交给用户前的最后一道质量保证工序,因而它决定了分选机的重要性。FX-120薄膜电容自动分选机主要进行容量不足检测、直流飞弧检测、直流双向耐压测试、损耗及容量测试并自动分选。主要介绍了该分选机的工作原理、基本机构、电气控制、气动控制、软件设计、关键技术及解决方案。 相似文献