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991.
磁控溅射Ge/Si多层膜X射线低角衍射界面结构分析 总被引:5,自引:1,他引:5
本文对磁控溅射不同结构的Ge/Si多层膜样品进行了X射线衍射的测试和分析,并进一步采用有过渡层的光学多层膜衍射模型对衍射谱进行了拟合;获得了扩散层厚度和分层厚度等多层膜的结构参数,定性讨论了多层膜中互扩散与分层厚度铁关系。计算结果与实验结果符合较好。 相似文献
992.
深入教育改革探索培养创新人才的新思路 总被引:2,自引:0,他引:2
为培养适应21世纪飞速发展的科技竞争需要的优秀人才,我们对现有培养模式所进行的教育改革中,作了一些尝试。吸取MIT等国外著名大学的成功办学经验,总结我院在原有教改试点班工作中所取得的成绩,组建了MIT电子信息试点班,并以此为突破口.寻求培养宽厚型创新人才的新思路,形成以信息为主线涉及多个学科基础理论的课程体系,带动面上教学。并论述了设立MIT电子信息试点班的必要性和可能性,介绍了该试点班的培养目标和培养特色。 相似文献
993.
介绍了键控特技的基本原理及分类,论述了键控特技应用于电视播出系统的必要性,并指出如何选择和使用适合于电视播出系统的键控混合器. 相似文献
994.
995.
Xu Shuiqing Chai Yi Hu Youqiang Huang Lei 《International Journal of Electronics》2018,105(6):1051-1062
Nonuniform sampling can be encountered in various practical processes because of random events or poor timebase. The analysis and applications of the nonuniform sampling for deterministic signals related to the linear canonical transform (LCT) have been well considered and researched, but up to now no papers have been published regarding the various nonuniform sampling theorems for random signals related to the LCT. The aim of this article is to explore the nonuniform sampling and reconstruction of random signals associated with the LCT. First, some special nonuniform sampling models are briefly introduced. Second, based on these models, some reconstruction theorems for random signals from various nonuniform samples associated with the LCT have been derived. Finally, the simulation results are made to prove the accuracy of the sampling theorems. In addition, the latent real practices of the nonuniform sampling for random signals have been also discussed. 相似文献
996.
Bocheng Bao Li Xu Zhimin Wu Mo Chen Huagan Wu 《International Journal of Electronics》2018,105(7):1159-1169
Based on a memristive diode bridge cascaded with series resistor and inductor filter, a modified memristive canonical Chua’s circuit is presented in this paper. With the modelling of the memristive circuit, a normalised system model is built. Stability analyses of the equilibrium points are performed and bifurcation behaviours are investigated by numerical simulations and hardware experiments. Most extraordinary in the memristive circuit is that within a parameter region, coexisting phenomenon of multiple bifurcation modes is emerged under six sets of different initial values, resulting in the coexistence of four sets of topologically different and disconnected attractors. These coexisting attractors are easily captured by repeatedly switching on and off the circuit power supplies, which well verify the numerical simulations. 相似文献
997.
Yanqiu Jiang Zhen Xu Tieqi Huang Yingjun Liu Fan Guo Jiabin Xi Weiwei Gao Chao Gao 《Advanced functional materials》2018,28(16)
Graphene aerogel microlattices (GAMs) hold great prospects for many multifunctional applications due to their low density, high porosity, designed lattice structures, good elasticity, and tunable electrical conductivity. Previous 3D printing approaches to fabricate GAMs require either high content of additives or complex processes, limiting their wide applications. Here, a facile ion‐induced gelation method is demonstrated to directly print GAMs from graphene oxide (GO) based ink. With trace addition of Ca2+ ions as gelators, aqueous GO sol converts to printable gel ink. Self‐standing 3D structures with programmable microlattices are directly printed just in air at room temperature. The rich hierarchical pores and high electrical conductivity of GAMs bring admirable capacitive performance for supercapacitors. The gravimetric capacitance (Cs) of GAMs is 213 F g?1 at 0.5 A g?1 and 183 F g?1 at 100 A g?1, and retains over 90% after 50 000 cycles. The facile, direct 3D printing of neat graphene oxide can promote wide applications of GAMs from energy storage to tissue engineering scaffolds. 相似文献
998.
Yi Song Huajie Zhou Qiuxia Xu Jun Luo Haizhou Yin Jiang Yan Huicai Zhong 《Journal of Electronic Materials》2011,40(7):1584-1612
The aggressive downscaling of complementary metal–oxide–semiconductor (CMOS) technology to the sub-21-nm technology node is
facing great challenges. Innovative technologies such as metal gate/high-k dielectric integration, source/drain engineering, mobility enhancement technology, new device architectures, and enhanced
quasiballistic transport channels serve as possible solutions for nanoscaled CMOS. Among them, mobility enhancement technology
is one of the most promising solutions for improving device performance. Technologies such as global and process-induced strain
technology, hybrid-orientation channels, and new high-mobility channels are thoroughly discussed from the perspective of technological
innovation and achievement. Uniaxial strain is superior to biaxial strain in extending metal–oxide–semiconductor field-effect
transistor (MOSFET) scaling for various reasons. Typical uniaxial technologies, such as embedded or raised SiGe or SiC source/drains,
Ge pre-amorphization source/drain extension technology, the stress memorization technique (SMT), and tensile or comprehensive
capping layers, stress liners, and contact etch-stop layers (CESLs) are discussed in detail. The initial integration of these
technologies and the associated reliability issues are also addressed. The hybrid-orientation channel is challenging due to
the complicated process flow and the generation of defects. Applying new high-mobility channels is an attractive method for
increasing carrier mobility; however, it is also challenging due to the introduction of new material systems. New processes
with new substrates either based on hybrid orientation or composed of group III–V semiconductors must be simplified, and costs
should be reduced. Different mobility enhancement technologies will have to be combined to boost device performance, but they
must be compatible with each other. The high mobility offered by mobility enhancement technologies makes these technologies
promising and an active area of device research down to the 21-nm technology node and beyond. 相似文献
999.
云计算的出现,改变了传统IT基础设施的使用方式和软件部署模式,并带来了大型云计算数据中心的建设热潮。本文阐述了全球数据中心的发展趋势,总结了数据中心发展的特点,并对我国数据中心发展的情况做了分析。 相似文献
1000.
Xi Chen Zhong-Chao FanYun Xu Guo-Feng SongLiang-Hui Chen 《Microelectronic Engineering》2011,88(9):2889-2893
We combine interferometric lithography and inductively coupled plasma etching to fabricate GaAs subwavelength grating (SWG) which mimics the moth eye structures. Through the modification of morphology parameters, including profile, height and packing fraction, tapered, high-aspect-ratio and closely-packed GaAs SWGs are obtained. The measurement of spectral reflectance of the fabricated SWGs shows that reflection has been dramatically reduced compared to the polished GaAs surface. Particularly, the optimized SWG structures exhibit an average reflection below 5% in the wavelengths ranging from 350 to 900 nm. Furthermore, the angular-independent property is demonstrated by measuring the reflectance versus varying angles of incidence at 532 and 632.8 nm wavelengths. 相似文献