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161.
制备了一种有机垂直光发射晶体管, 兼具有机发光二极管的发光和晶体管的开关调节两个功能.其结构为一个有机发光单元垂直堆叠在一个电容单元上,两单元通过一个共有的源电极连在一起.当电容单元被充电时,积累在源电极的电荷能有效地调节源极与有机层之间的载流子注入势垒,从而达到控制源漏输出电流的大小,最终控制发光单元发光的强度.实验结果表明,器件可提供02 mA的输出电流,其大小可驱动发光单元发光,工作电压(开启电压)为6 V.这种垂直集成方案,实现了器件多功能化,为有机发光二极管有源矩阵驱动的实际应用提供了一种新的解决方法. 关键词: 有机光发射晶体管 垂直 电容  相似文献   
162.
Juan Li  Li Cui 《Applied Surface Science》2010,256(13):4339-23590
One-dimensional nanostructured manganese dioxide/polypyrrole (MnO2/PPy) composite was prepared by in situ chemical oxidation polymerization of pyrrole in the host of inorganic matrix of MnO2, using complex of methyl orange (MO)/FeCl3 as a reactive self-degraded soft-template. The morphology and structure of the composite were characterized by infrared spectroscopy (IR) X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the MnO2/PPy composite consists of α-MnO2 and PPy with nanotube-like structure. Electrochemical properties of the composite demonstrated the material showed good electrochemical reversibility after 500 charge-discharge cycles in the potential range of −0.4 to 0.6 V, the tube-like nanocomposite has the potential application in electrochemical capacitor.  相似文献   
163.
从生态设计的基本理念对生态设计与企业经营模式间的关系,提出若干建议;并对电子组装基板生态循环模式的建立、电子整机产品生态设计要点作了简单的分析介绍。  相似文献   
164.
一种电容间隙精确可控的高对称加速度传感器   总被引:1,自引:0,他引:1  
提出了一种高对称电容式微加速度传感器,该传感器为硅四层键合三明治结构,在完成传感器整体结构制作的同时,实现了圆片级真空封装。利用多次氧化的方法,既精确控制了加速度传感器的初始电容间距,又实现了限位凸点的制作。该加速度传感器的谐振频率为657Hz,品质因子为198,灵敏度为0.59V/g。  相似文献   
165.
利用半导体pn结结电容构成的沟道式电容器   总被引:1,自引:0,他引:1  
为满足对电子系统中元器件性能提升、面积减小、成本降低等需求,利用感应耦合等离子体刻蚀技术(ICP),对低阻p型硅采用刻蚀、扩散、磁控溅射Al电极等工艺,使之形成凹槽状三维结构,制造出一种特殊的具有高密度电容量的硅基电容器。其特点是结构简单,电容量大(电容密度可达2.2×10–9F/mm2),容值可调,与现有微电子工艺兼容,可用于200MHz至数GHz的退耦或其他场合。同时由于半导体pn结固有的特性,该电容器可取代传统的贴片电容广泛用于电子系统中的退耦、滤波、匹配、静电和电涌防护等场合。  相似文献   
166.
以具有电容降压电路的房问电加热器浪涌抗扰度不合格的典型案例为研究对象,给出了详细的定位与验证分析过程,并提出了整改措施,即在整流桥输出到稳压二极管之间串联限流电阻。整改后,房间电加热器满足浪涌抗扰度要求,即火线对零线(差模)±1kV,火线对地线(共模)±2kV,零线对地线(共模)±2kV。  相似文献   
167.
In this paper, we focus on investigating the asymptotic stabilizability of switched systems with input time delay and its applications in networked control systems (NCSs). First, based on an important lemma, a linear matrix inequality (LMI)-based asymptotic stabilizability criterion is established. Stabilizing switched state feedback controllers can be designed by solving a set of LMIs, which can be easily tested with efficient LMI algorithms. Then, for NCSs with communication constraints, the NCS is modelled as a discrete-time switched system with input time delay. Thus, the asymptotic stabilizability criterion of switched system with input delay can be applicable to such NCSs. Finally, an example is given to illustrate our main results. This work is supported by the National Natural Science Foundation of China under grants (No. 60704015), a grant of Liuhui Center for Applied Mathematics of Nankai University and Tianjin University in China.  相似文献   
168.
The paper presents a systematic investigation of dielectric charging in low temperature silicon nitride for RF-MEMS capacitive switches. The dielectric charging is investigated with the aid of Metal-Insulator-Metal (MIM) capacitors with different thickness dielectric film and symmetric and asymmetric metal contacts. The experimental results demonstrate that the charging process is almost symmetric in low temperature deposited silicon nitride. Experiments performed in both MIM and MEMS reveal that the charging process is strongly affected by temperature. Specifically at high temperatures the charging rate increases exponentially with temperature.  相似文献   
169.
The global uniform exponential stability of switched positive linear impulsive systems with time-varying delays and all unstable subsystems is studied in this paper, which includes two types of distributed time-varying delays and discrete time-varying delays. Switching behaviors dominating the switched systems can be either stabilizing and destabilizing in the new designed switching sequence. We design new linear programming algorithm process to find the feasible ratio of stabilizing switching behaviors, which can be compensated by unstable subsystems, destabilizing switching behaviors, and impulses. Speci cally, we add a kind of nonnegative impulses which is consistent with the switching behaviors for the systems. Employing a multiple co-positive Lyapunov-Krasovskii functional, we present several new sufficient stability criteria and design new switching sequence. Then, we apply the obtained stability criteria to the exponential consensus of linear delayed multi-agent systems, and obtain the new exponential consensus criteria. Three simulations are provided to demonstrate the proposed stability criteria.  相似文献   
170.
A novel shielding scheme is developed by inserting a concave shield between a metal–insulator–metal (MIM)capacitor and the silicon substrate.Chip measurements reveal that the concave shield improves the quality factor by 11%at 11.8 GHz and 14%at 18.8 GHz compared with an unshielded MIM capacitor.It also alleviates the effect on shunt capacitance between the bottom plate of the MIM capacitor and the shield layer.Moreover,because the concave shields simplify substrate modeling,a simple circuit model of the MIM capacitor with concave shield is presented for radio frequency applications.  相似文献   
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