共查询到20条相似文献，搜索用时 15 毫秒
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An accumulation channel trench gate insulated gate bipolar transistor (ACT-IGBT) is proposed. The simu-lation results show that for a blocking capability of 1200 V, the on-state voltage drops of ACT-IGBT are 1.5 and 2 V at a temperature of 300 and 400 K, respectively, at a collector current density of 100 A/cm~2. In contrast, the on-state voltage drops of a conventional trench gate IGBT (CT-IGBT) are 1.7 and 2.4 V at a temperature of 300 and 400 K,respectively. Compared to the CT-IGBT, the ACT-IGBT has a lower on-state voltage drop and a larger forward bias safe operating area. Meanwhile, the forward blocking characteristics and turn-off performance of the ACT-IGBT are also analyzed. 相似文献
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Inspired by the light‐driven, cross‐membrane proton pump of biological systems, a photoelectric conversion system based on a smart‐gating, proton‐driven nanochannel is constructed. In this system, solar energy is the only source of cross‐membrane proton motive force that induces a diffusion potential and photocurrent flowing through the external circuit. Although the obtained photoelectric conversion performance is lower than that of conventional solid photovoltaic devices, it is believed that higher efficiencies can be generated by enhancing the protonation capacity of the photo‐acid molecules, optimizing the membrane, and synthesizing high‐performance photosensitive molecules. This type of facile and environmentally friendly photoelectric conversion has potential applications for future energy demands such as the production of power for in vivo medical devices. 相似文献
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Qianqian Zhang Zhaoyue Liu Kefeng Wang Jin Zhai 《Advanced functional materials》2015,25(14):2091-2098
Inspired by the asymmetric structure and responsive ion transport in biological ion channels, organic/inorganic hybrid artificial nanochannels exhibiting pH‐modulated ion rectification and light‐regulated ion flux have been constructed by introducing conductive polymer into porous nanochannels. The hybrid nanochannels are achieved by partially modifying alumina (Al2O3) nanopore arrays with polypyrrole (PPy) layer using electrochemical polymerization, which results in an asymmetric component distribution. The protonation and deprotonation of Al2O3 and PPy upon pH variation break the surface charge continuity, which contributes to the pH‐tunable ion rectification. The ionic current rectification ratio is affected substantially by the pH value of electrolyte and the pore size of nanochannels. Furthermore, the holes (positive charges) in PPy layer induced by the cooperative effect of light and protons are used to regulate the ionic flux through the nanochannels, which results in a light‐responsive ion current. The magnitude of responsive ionic current could be amplified by optimizing this cooperation. This new type of stimuli‐responsive PPy/Al2O3 hybrid nanochannels features advantages of unique optical and electric properties from conducting PPy and high mechanical performance from porous Al2O3 membrane, which provide a platform for creating smart nanochannels system. 相似文献
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Charge injection/blocking layers play important roles in the performances of organic electronic devices. Their incorporation into organic light emitting transistors has been limitted, due to generally high operating voltages (above 60 V) of these devices. In this work, two hole blocking molecules are integrated into tris-(8-hydroxyquinoline) aluminum (Alq3) based light emitting transistors under operating voltage as low as 5 V. The effects of hole blocking and electron injection are decoupled through the differences in the energy levels. Significantly improved optical performance is achieved with the molecule of suitable energy level for electron injection. Surprisingly, a decreased performance is observed in the case of another hole blocking molecule evidencing that charge injection overweighs charge blocking in this device architecture. 相似文献
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分析了传统晶闸管结终端造型技术的优缺点.基于双负角结终端造型技术,通过径向变掺杂技术和类台面造型技术改进,发展了一种全新的结终端造型技术.该技术不仅使芯片极薄化,而且使结终端造型占用芯片长度极小化,同时使有效导通长度极大化.制造并测试了三种不同结终端造型技术的样品,测试结果表明,采用该技术的样品在不降低阻断电压(≥8 000 V)前提下,具有更小的漏电流(2.50 mA);在流过相同的通态电流(4 500 A)时,具有更小的通态压降1.782 V;而且反向恢复电荷、dv/dt耐量、di/dt耐量、关断时间等得到全面优化.成功研制了6英寸(1英寸=2.54 cm)电流为4 500 A、阻断电压为8 500 V的特高压晶闸管,其动态特性和参数的一致性满足设计及应用要求. 相似文献
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According to the avalanche ionization theory,a computer-based analysis is performed to analyze the structural parameters of single-and multiple-zone junction termination extension (JTE) structures for 4H-SiC bipolar junction transistors (BJTs) with mesa structure.The calculation results show that a single-zone JTE can yield high breakdown voltages if the activated JTE dose and the implantation width are controlled precisely and a multiple-zone JTE method can decrease the peak surface field while still maintaining a high blocking capability.The influences of the positive and negative surface or interface states on the blocking capability are also shown.These conclusions have a realistic meaning in optimizing the design of a mesa power device. 相似文献
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将新器件结构与新型半导体材料相结合,提出了一种新型的n-区三层渐变掺杂理想欧姆接触型p+(SiGeC)-n-n+异质结功率二极管,并对n-区的杂质分布梯度进行了优化.基于MEDICI,给出了该结构的关键物理参数模型,并在此基础上对新结构的设计思路和工作原理进行了全面分析.结果表明,与常规理想欧姆接触结构相比,该新结构在保持快而软反向恢复特性的前提下,反向阻断电压增加了近一倍,而且正向通态特性也有所改善,很好地实现了功率二极管中Qs-Vf-Ir三者的良好折中. 相似文献
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台面结终端高压4H-SiC BJTs的击穿特性研究 总被引：1，自引：1，他引：0
根据雪崩碰撞理论,本文对具有台面结构的4H-SiC BJTs中所使用的单区和多区结终端结构参数对击穿电压的影响进行了分析和计算。计算结果表明,在单区结终端结构中,通过精确控制有源JTE的掺杂浓度和离子注入深度可以有效提高台面BJTs器件的击穿电压,而多区结终端结构可以在保持击穿电压不变的前提下降低峰值表面电场。同时文中还对正负表面态或界面态对击穿电压的影响做了详细的计算分析。这些结果对于优化台面功率器件的高压特性有着重要的现实意义。 相似文献
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Juntao Li Chengquan Xiao Xingliang Xu Gang Dai Lin Zhang Yang Zhou An Xiang Yingkun Yang Jian Zhang 《半导体学报》2017,38(2):024003-4
This paper presents the design and fabrication of an etched implant junction termination extension(JTE) for high-voltage 4H-SiC PiN diodes. Unlike the conventional JTE structure, the proposed structure utilizes multiple etching steps to achieve the optimum JTE concentration range. The simulation results show that the etched implant JTE method can improve the blocking voltage of SiC PiN diodes and also provides broad process latitude for parameter variations, such as implantation dose and activation annealing condition. The fabricated SiC PiN diodes with the etched implant JTE exhibit a highest blocking voltage of 4.5 kV and the forward on-state voltage of 4.6 V at room temperature. These results are of interest for understanding the etched implant method in the fabrication of high-voltage power devices. 相似文献
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将新器件结构与新型半导体材料相结合,提出了一种新型的n-区三层渐变掺杂理想欧姆接触型p (SiGeC)-n-n 异质结功率二极管,并对n-区的杂质分布梯度进行了优化.基于MEDICI,给出了该结构的关键物理参数模型,并在此基础上对新结构的设计思路和工作原理进行了全面分析.结果表明,与常规理想欧姆接触结构相比,该新结构在保持快而软反向恢复特性的前提下,反向阻断电压增加了近一倍,而且正向通态特性也有所改善,很好地实现了功率二极管中Qs-Vf-Ir三者的良好折中. 相似文献
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报道了在150 μm厚、掺杂浓度5.0×1014 cm-3的外延层上制备15 kV/10 A超高压SiC功率MOSFET器件的研究结果。对器件原胞结构开展了仿真优化,基于材料结构、JFET区宽度和JFET区注入掺杂等条件优化,有效地提升了器件的导通能力,器件比导通电阻为204 mΩ·cm2,击穿电压大于15.7 kV,在漏极电压15 kV时,器件漏电流为10 μA,漏电流密度为12 μA·cm-2。在工作电压1.7 kV、导通电流10 A条件下,开通时间和关断时间分别为140 ns和 84 ns。 相似文献
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Youtian Tao Qiang Wang Chuluo Yang Cheng Zhong Jingui Qin Dongge Ma 《Advanced functional materials》2010,20(17):2923-2929
A new triphenylamine/oxadiazole hybrid, namely m‐TPA‐o‐OXD, formed by connecting the meta‐position of a phenyl ring in triphenylamine with the ortho‐position of 2,5‐biphenyl‐1,3,4‐oxadiazole, is designed and synthesized. The new bipolar compound is applicable in the phosphorescent organic light‐emitting diodes (PHOLEDs) as both host and exciton‐blocking material. By using the new material and the optimization of the device structures, very high efficiency green and yellow electrophosphorescence are achieved. For example, by introducing 1,3,5‐tris(N‐phenylbenzimidazol‐2‐yl)benzene (TPBI) to replace 2, 9‐dimethyl‐4,7‐diphenyl‐1, 10‐phenanthroline (BCP)/tris(8‐hydroxyquinoline)aluminium (Alq3) as hole blocking/electron transporting layer, followed by tuning the thicknesses of hole‐transport 1, 4‐bis[(1‐naphthylphenyl)amino]biphenyl (NPB) layer to manipulate the charge balance, a maximum external quantum efficiency (ηEQE,max) of 23.0% and a maximum power efficiency (ηp,max) of 94.3 lm W−1 are attained for (ppy)2Ir(acac) based green electrophosphorescence. Subsequently, by inserting a thin layer of m‐TPA‐o‐OXD as self triplet exciton block layer between hole‐transport and emissive layer to confine triplet excitons, a ηEQE,max of 23.7% and ηp,max of 105 lm W−1 are achieved. This is the highest efficiency ever reported for (ppy)2Ir(acac) based green PHOLEDs. Furthermore, the new host m‐TPA‐o‐OXD is also applicable for other phosphorescent emitters, such as green‐emissive Ir(ppy)3 and yellow‐emissive (fbi)2Ir(acac). A yellow electrophosphorescent device with ηEQE,max of 20.6%, ηc,max of 62.1 cd A−1, and ηp,max of 61.7 lm W−1, is fabricated. To the author’s knowledge, this is also the highest efficiency ever reported for yellow PHOLEDs. 相似文献
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利用一台毛细管快放电X射线激光装置．研究了预脉冲作用下氩气和氦气在10～120Pa压强范围内对毛细管放电的击穿特性。实验结果表明只有10～15kV放电电压才能将内径为3mm．长度为90mm的毛细管中10～120Pa的氩气击穿，同时电极表面的形态对击穿电位也有较大影响。对预、主脉冲作用下毛细管放电规律及Z箍缩过程中阻抗变化规律进行了研究，发现不同长度的氩气柱在箍缩过程中的阻抗变化趋势基本相同。不同长度、不同放电电压情况下，毛细管阻抗均达到最小值5n左右．同时电流达到峰值。该结果为在相同放电电压下．对不同长度毛细管放电获得相同的电流峰值提供了可能。 相似文献
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In this paper, we present a low‐voltage low‐dropout voltage regulator (LDO) for a system‐on‐chip (SoC) application which, exploiting the multiplication of the Miller effect through the use of a current amplifier, is frequency compensated up to 1‐nF capacitive load. The topology and the strategy adopted to design the LDO and the related compensation frequency network are described in detail. The LDO works with a supply voltage as low as 1.2 V and provides a maximum load current of 50 mA with a drop‐out voltage of 200 mV: the total integrated compensation capacitance is about 40 pF. Measurement results as well as comparison with other SoC LDOs demonstrate the advantage of the proposed topology. 相似文献
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目前自供电无线压电传感器网络已被广泛应用在智能家居及环境监测等领域.组成网络的每个压电传感器节点需要完成不同功耗的任务,如数据采集、存储等低功耗任务和数据无线传输的高功耗任务.针对低功耗和高功耗任务,该文设计了基于新型欠压闭锁电路的双模组能量收集电路,电路具有蓄能周期短和容量大的特点,可分别用于低功耗任务的低功耗级蓄能... 相似文献