共查询到19条相似文献，搜索用时 828 毫秒
1.
2.
张琼 《科技成果管理与研究》2021,16(7):46-47
半导体的光学性质是半导体最重要的物理性质之一,主要研究辐射场与半导体的相互作用过程.对半导体光学性质的研究一方面探索辐射在半导体中产生、传播、湮没、散射及其在界面处出射行为的规律,另一方面又提供了有关半导体电子能带结构、声子结构、束缚和自由载流子行为等基本物理信息.基于这些研究,近20年来,光学方法已经成为检测和标定半导体材料物理性质最基本、最重要的手段而被广泛应用.同时正是这些研究及其成果开拓了半导体应用的新领域,例如,半导体辐射探测、激光、发光、太阳能光电转换等各种光电转换、电光转换和其他转换过程的器件,以及目前正迅速发展的各种非线性光学、光电信息、光子信息应用. 相似文献
3.
4.
《黑龙江科技信息》2017,(16)
半导体材料作为场效应晶体管的关键组成元素,严重的影响器件性能,相对于小分子半导体材料,聚合物半导体材料具有很多优势,比如便于溶液加工、适用于室温制备等。目前,高迁移率聚合物半导体材料经过多年研发,已经取得了突飞猛进的成果,并且经过不断的创新,诞生了各种结构新颖、性能良好的聚合物半导体材料,不断优化器件制备工艺,使得聚合物场效应晶体管的载流子迁移率从10~(-5_cm~2v~(-1)s~(-1)提升到了36.3cm2v~(-1)s~(-1)。详细地描述了高迁移率聚合物半导体材料的研究现状,分析了高迁移率聚合物在半导体器件设计中的应用情况,从空穴传输型、电子传输型和双极传输型等三个方面分析高迁移率聚合物半导体研发现状,归纳和总结半导体材料,从而可以进一步的为半导体器件构筑提供一定的指导。 相似文献
5.
氮化镓，是直接带隙半导体材料，在室温下有很宽的带隙（3.39eV）。它在光电子器件如蓝光、紫外、紫光等光发射二极管和激光二极管方面有着重要的应用。本文系统地介绍了氮化镓的各种制备方法，对其结构和性能关系的研究,揭示了它在半导体领域广泛且重要的应用前景。 相似文献
6.
自从上世纪90年代至今,人们一直致力于第三代半导体——宽带隙半导体的研究,其基本应用在紫外一蓝紫波段的短波长发光器件,主要包括发光二极管（LEDs）和激光器（LDs）。宽带半导体LEDs不仅具有节能、寿命长等优点,而且是一种高温、高功率器件,应用广泛,有着数百亿的巨大市场。目前,在短波长LEDs领域, 相似文献
7.
基于第一性原理总能量平面波全势方法,采用广义梯度近似（ＧＧＡ）和局域密度近似（ＬＤＡ）等不同的交换关联势,计算了体心结构ＰｂＳ的总能,并给出了体系平衡时的晶格常数．讨论了不同交换关联势对能带结构、态密度、分态密度及能隙的影响．与面心结构ＰｂＳ结果对比,能量的计算结果表明,面心结构ＰｂＳ较体心结构更稳定．另外,体心结构ＰｂＳ的能带计算结果表明存在能隙,这与同族铅盐化合物中存在能隙的实验结论一致．上述ＰｂＳ的计算结果有助于实验研究． 相似文献
8.
半导体超晶格微结构是理想的技术上能很好控制的低维物理系统，是一大类以“能带工程”为设计依据和以分子束外延（ＭＢＥ）技术为基础的新型人工材料，具有重大的光电子和微电子器件应用前景。８０年代以来，作为物理、材料与器件３者的结合点，半导体超晶格微结构一直是半导体科学最活跃的研究前沿领域。黄昆及其合作者自１９８６年开展超晶格电子态和声子模理论研究以来，对光学声子模式和激子态理论的发展做出了关键性的重要贡献，在电子态理论上发展了有自己特色的计算方法。超晶格振动是超晶格物理的基础。准二维量子结构中的光学振动… 相似文献
9.
闪锌矿型CdTe电子结构和光学性质的第一性原理 总被引：4，自引：0，他引：4
采用基于密度泛函理论(DFT)框架下广义梯度近似平面波超软赝势法,计算了闪锌矿型CdTe的能带结构、态密度和光学性质.计算表明,闪锌矿型CdTe为直接带隙半导体,禁带宽度为0.671eV.计算并分析了闪锌矿型CdTe的复折射率、复介电函数、吸收系数、光电导率、损失函数和反射率,其折射率为2.69,静态介电常数为7.23.计算结果与其他文献结果吻合较好,为闪锌矿型CdTe的应用提供了理论依据. 相似文献
10.
11.
ＳＹＮＴＨＥＳＩＳＡＮＤＰＲＯＰＥＲＴＩＥＳＯＦＨＥＰＡＲＩＮＩＺＥＤＰＯＬＹＭＥＴＨＡＣＲＹＬＩＣＡＣＩＤ￥ＦｅｎｇＰｉｎｚｈｅｎ；ＬｕＪｉａｎｔａｏ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＧｒａｄｕａｔｅＳｃｈｏｏｌ，ＡｃａｄｅｍｉａＳｉｎ... 相似文献
12.
《Journal of The Franklin Institute》2019,356(14):7731-7753
Since being postulated more than a decade ago, inerters have been successfully employed to enhance the dynamic performance of mechanical systems in several applications. Their ability to lend a high dynamic mass presence to systems that employ them with only a relatively small static device mass makes them unique among mechanical elements. This study explores the mechanical wave manipulation characteristics of nonlinear inertant acoustic metamaterial (NLIAM) configurations using analysis and simulations for their one-dimensional discrete element lattice representations. Firstly, based on notional concepts for nonlinear inertant devices, potential frequency-dependent and acceleration-dependent nonlinear inertant models are identified. Using an effective mass model for the NLIAM with frequency-dependent inertance in the local resonator attachment, the dispersion characteristics of inverse square law and power law inertance models are examined and contrasted with those for an acoustic metamaterial with frequency invariant inertance. While a tuned inverse square law inertance model ensures the existence of a band gap over almost the entire frequency bandwidth of interest even encompassing the extremely low frequency regime, the low and high frequency limits for this inertance law would not be realizable in practice. A potentially more practical power law approximation is proposed and shown to deliver a widening of the band gap by more than 100% towards frequencies below the lower bound of the band gap for the acoustic metamaterial with frequency invariant inertance. Further, drawing inspiration from the Duffing-type stiffness, an acceleration-dependent cubically nonlinear inertance model is proposed. First order corrections to the dispersion characteristics are obtained for an NLIAM with acceleration-dependent inertance using a perturbation approach. For weakly nonlinear cases, excitation amplitude-activated shifts in the dispersion curves are found to enable this NLIAM to act as a passive adaptive filter for mechanical waves based solely on their excitation amplitude. Practical manifestations of such NLIAM could therefore provide a means to realize extraordinary wave manipulation capabilities especially suitable for low frequency structural dynamic applications. 相似文献
13.
Junya Suehiro 《Biomicrofluidics》2010,4(2)
Dielectrophoresis (DEP) is an electrokinetic motion of dielectrically polarized materials in nonuniform electric fields. DEP has been successfully applied to manipulation of nanomaterials including carbon nanotubes (CNTs), metallic nanoparticles, and semiconducting nanowires. Under positive DEP force, which attracts nanomaterials toward the higher field region, nanomaterials are trapped in the electrode gap and automatically establish good electrical connections between them and the external measuring circuit. This feature allows us a fast, simple, and low-cost fabrication of nanomaterial-based sensors based on a bottom-up approach. This paper first presents a theoretical background of DEP phenomena and then reviews recent works of the present author, which were aimed to develop nanomaterial-based sensors, such as a CNT gas sensor and a ZnO nanowire photosensor, using DEP fabrication technique. It is also demonstrated that DEP technique enables self-formation of interfaces between various nanomaterials, which can be also applicable as novel sensing transducers. 相似文献
14.
运用频域有限元法研究了金属铜介质柱构成的二维光子晶体传输特性。通过改变铜柱形状和大小,研究了晶格常数为200μm的正方晶格光子晶体的TM模、TE模的禁带特性。选取金属铜为介质柱,空气为背景材料,对正方铜柱与旋转45度正方铜柱进行了大量计算与分析。结果表明,传输特性随着介质柱形状和填充率的变化而变化,且TE模和TM模带隙差异很大,波段并不相同,这为THz波段的光子晶体滤波器、反射器、极化器的开发与制作提供了理论依据。 相似文献
15.
脂肪族聚酯是最重要的一类可生物降解聚合物，其合成过程中多采用含金属元素的催化剂，残留的金属元素会对其生物相容性和环境相容性造成不利的影响，因而，采用无毒的非金属催化剂成为脂肪族聚酯合成中备受关注的课题。本文对非金属催化剂催化合成脂肪族聚酯的研究进展进行综述。 相似文献
16.
Ronald Pethig 《Biomicrofluidics》2010,4(2)
A review is presented of the present status of the theory, the developed technology and the current applications of dielectrophoresis (DEP). Over the past 10 years around 2000 publications have addressed these three aspects, and current trends suggest that the theory and technology have matured sufficiently for most effort to now be directed towards applying DEP to unmet needs in such areas as biosensors, cell therapeutics, drug discovery, medical diagnostics, microfluidics, nanoassembly, and particle filtration. The dipole approximation to describe the DEP force acting on a particle subjected to a nonuniform electric field has evolved to include multipole contributions, the perturbing effects arising from interactions with other cells and boundary surfaces, and the influence of electrical double-layer polarizations that must be considered for nanoparticles. Theoretical modelling of the electric field gradients generated by different electrode designs has also reached an advanced state. Advances in the technology include the development of sophisticated electrode designs, along with the introduction of new materials (e.g., silicone polymers, dry film resist) and methods for fabricating the electrodes and microfluidics of DEP devices (photo and electron beam lithography, laser ablation, thin film techniques, CMOS technology). Around three-quarters of the 300 or so scientific publications now being published each year on DEP are directed towards practical applications, and this is matched with an increasing number of patent applications. A summary of the US patents granted since January 2005 is given, along with an outline of the small number of perceived industrial applications (e.g., mineral separation, micropolishing, manipulation and dispensing of fluid droplets, manipulation and assembly of micro components). The technology has also advanced sufficiently for DEP to be used as a tool to manipulate nanoparticles (e.g., carbon nanotubes, nano wires, gold and metal oxide nanoparticles) for the fabrication of devices and sensors. Most efforts are now being directed towards biomedical applications, such as the spatial manipulation and selective separation∕enrichment of target cells or bacteria, high-throughput molecular screening, biosensors, immunoassays, and the artificial engineering of three-dimensional cell constructs. DEP is able to manipulate and sort cells without the need for biochemical labels or other bioengineered tags, and without contact to any surfaces. This opens up potentially important applications of DEP as a tool to address an unmet need in stem cell research and therapy. 相似文献
17.
18.
概述了高分子材料聚乙烯醇的发展现状,对以甘蔗为原料开发"生物质乙烯制生物基高分子材料-聚乙烯醇"产品的发展,市场、技术、经济等方面的优势进行了深入分析,阐明了不断发展生物质乙烯法制生物基高分子材料聚乙烯醇等生物质化工产业群是广西生物质甘蔗深化利用的有效途径。 相似文献
19.
阐述了再生混凝土技术的发展历程,以及在工程中的应用情况,分析了其在工程应用中的可行性和工程应用价值,表明了再生混凝土在未来的发展前景,并为今后对再生混凝土的研究做指导。 相似文献