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Simulation of near-infrared photodiode detectors based on β-FeSi_2/4H-SiC heterojunctions 总被引:1,自引:0,他引:1 下载免费PDF全文
In this paper,we propose a near-infrared p-type β-FeSi2/n-type 4H-SiC heterojunction photodetector with semiconducting silicide(β-FeSi2) as the active region for the first time.The optoelectronic characteristics of the photodetector are simulated using a commercial simulator at room temperature.The results show that the photodetector has a good rectifying character and a good response to near-infrared light.Interface states should be minimized to obtain a lower reverse leakage current.The response spectrum of the β-FeSi2/4H-SiC detector,which consists of a p-type β-FeSi2 absorption layer with a doping concentration of 1×1015cm-3 and a thickness of 2.5 μm,has a peak of 755 mA/W at 1.42 μm.The illumination of the SiC side obtains a higher responsivity than that of the β-FeSi2 side.The results illustrate that the β-FeSi2/4H-SiC heterojunction can be used as a near-infrared photodetector compatible with near-infrared optically-activated SiC-based power switching devices. 相似文献
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通过置换法在铝板上快速制备了一种即插即用型的Al/Ag纳米表面增强拉曼光谱(SERS)活性基底。结果表明该SERS基底较好地解决了银纳米颗粒在支撑物质上的吸附问题,能够快速实现对三聚氰胺的检测,而且具有操作简单、成本低、无损伤检测等优点,最低检测浓度能达到10^-7 mol·L^-1,满足国家食品安全要求的最低标准。另外,Al/Ag活性基底对三聚氰胺检测具有较高的拉曼测试重现性,连续测定15 h的过程中拉曼强度波动不大;且该Al/Ag活性基底能够在三乙醇胺、N,N-二甲基甲酰胺和1,2-丙二胺等胺类物质中实现对三聚氰胺的选择性检测。 相似文献
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基于金纳米簇强烈的量子限制效应(strong quantum confinement effect,SQCE),采用一步合成法,制备了同时具有高效近红外荧光与CT双模态成像能力的超小金纳米簇.实验表明,通过优化合成比例以及合成条件,所合成的超小金纳米簇具有很大的斯托克斯(Stokes)位移、较高的荧光强度和X射线吸收效率.除此之外,该超小金纳米簇具有良好的单分散性、稳定性和生物相容性.4T1肿瘤细胞荧光成像实验结果表明,该纳米粒子可被肿瘤细胞快速、高效地摄取. 相似文献
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Optically controlled SiCGe/SiC heterojunction transistor with charge-compensation layer 总被引:1,自引:0,他引:1 下载免费PDF全文
A novel optically controlled SiCGe/SiC heterojunction transistor with charge-compensation technique has been simulated by using commercial simulator.This paper discusses the electric field distribution,spectral response and transient response of the device.Due to utilizing p-SiCGe charge-compensation layer,the responsivity increases nearly two times and breakdown voltage increases 33%.The switching characteristic illustrates that the device is latch-free and its fall time is much longer than the rise time.With an increase of the light power density and wavelength,the rise time and fall time will become shorter and longer,respectively.In terms of carrier lifetime,a compromise should be made between the responsivity and switching speed,the ratio of them reaches maximum value when the minority carrier lifetime equals 90 ns. 相似文献
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珠心算作为中华民族的文化瑰宝,以其视、听、触觉等多种感官的共同参与,有效开发幼儿脑潜能、建立脑映象、促进促进幼儿日后全面发展。在多年的教学实践中,我们体会到激发幼儿学习珠心算的兴趣,是学好珠心算、有效开发脑潜能的关键。 相似文献
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This paper develops a new and easy to implement analytical model for the specific on-resistance and electric field distribution along the critical path for 4H-SiC multi-floating junction Schottky barrier diode. Considering the charge compensation effects by the multilayer of buried opposite doped regions, it improves the breakdown voltage a lot in comparison with conventional one with the same on-resistance. The forward resistance of the floating junction Schottky barrier diode consists of several components and the electric field can be understood with superposition concept, both are consistent with MEDICI simulation results. Moreover, device parameters are optimized and the analyses show that in comparison with one layer floating junction, multilayer of floating junction layer is an effective way to increase the device performance when specific resistance and the breakdown voltage are traded off. The results show that the specific resistance increases 3.2 mΩ·cm 2 and breakdown voltage increases 422 V with an additional floating junction for the given structure. 相似文献
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三峡水库溶解有机质的三维荧光光谱研究 总被引:2,自引:0,他引:2
在三峡水库首次蓄水175 m最高水位及其消落至145 m最低水位期间, 分别采集三峡水库 8个段面的水样, 应用三维荧光光谱(EEM)研究了三峡水库中溶解有机质(DOM), 考察了DOM在整个三峡水库的组成、分布及其来源, 着重探讨了30 m水位消落对DOM的影响, 并拟合了DOM中各荧光峰强的比值变化及其与pH、溶解氧(DO)、溶解有机碳(DOC)、氧化还原电位(ORP)等环境因子的线性关系. 结果显示, 水库干流DOM的EEM均表现出4个荧光峰, 归属为类蛋白质、类腐殖酸、类富里酸. 最高水位时, 从三峡水库上游至下游, 荧光峰强逐渐增强, 在大坝前最强|最低水位时, 荧光峰强较其高水位均显著提高, 受丰水期沿岸不同的陆源汇流影响, 最强荧光峰出现在三峡水库中、上游. 各荧光峰强与环境因子的线性关系在枯水期高水位时较好, 在丰水期低水位时仅有DO与类蛋白有正相关性. 揭示了三峡水库水质主要受丰水期的陆源汇流影响, 而大坝运行模式的影响不显著. 相似文献
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电子导电金属有机框架是一类兼具导电性和多孔性的新型固体导电材料, 目前在燃料电池、电催化、超级电容器、热电、传感等电学领域得到广泛研究. 由于导电金属有机框架材料不易加工成膜, 阻碍了其在电子器件领域的进一步发展, 因此近年来导电金属有机框架薄膜及其电学性能的研究备受关注. 从电子导电金属有机框架薄膜的制备方法及其在电学领域中的应用出发, 总结了该类电学材料最新的研究进展, 并对其今后发展所面临的机遇和挑战进行了简单展望. 相似文献