共查询到18条相似文献,搜索用时 109 毫秒
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低阻硅衬底上形成的低损耗共平面波导传输线 总被引:1,自引:0,他引:1
在厚膜多孔硅 (PS) /氧化多孔硅 (OPS)衬底上 ,结合聚酰亚胺涂层改善表面 ,研制低损耗、高性能射频 (RF) /微波 (MW)共平面波导CPW(CoplanarWaveguide) .通过在N和P型硅上形成不同厚度PS膜 ,并对其上的CPW进行分析比较 ,厚膜PS与石英的共面波导插入损耗非常接近 ,远小于在 2 0 0 0Ω·cm高阻硅上形成的多晶硅 -氧化硅组合衬底 :在 0 33GHz范围 ,插入损耗小于 5dB/ 1.2cm ;33 4 0GHz范围 ,小于 7.5dB/ 1.2cm . 相似文献
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在适当条件下氧化多孔硅是提高多孔硅发光强度的良好途径。首次采用含CH3CSNH2的HF酸水溶液作为氧化剂对初始多孔硅进行了湿法阳极氧化,大大改善了多孔硅的发光强度,并研究了氧化电流密度、氧化温度、氧化时间等一系列因素对氧化多孔硅光致发光强度的影响。实验发现,在电流密度1mA/cm^2,氧化液温度60℃,氧化时间为10min的条件下,可以获得最强光致发光;在此最优条件下得到的氧化样品较初始样品发光增强了18倍。 相似文献
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氧化多孔硅周期性波导光栅耦合器的实验研究 总被引:1,自引:0,他引:1
报道了用两束相干激光在HF溶液中的多孔Si(PS)表面上干涉形成光强周期分布,通过光溶解得到了孔隙率周期变化的结构,从而制备出氧化PS周期性波导光栅。实现了辐射模与波导中传输模之间的耦合,并由外部入射光波或衍射光的方向确定了波导层的有效折射率。 相似文献
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Oxidized Porous Silicon Nanostructures Enabling Electrokinetic Transport for Enhanced DNA Detection 下载免费PDF全文
Nanostructured porous silicon (PSi) is a promising material for the label‐free detection of biomolecules, but it currently suffers from limited applicability due to poor sensitivity, typically in micromolar range. This work presents the design, operation concept, and characterization of a novel microfluidic device and assay that integrates an oxidized PSi optical biosensor with electrokinetic focusing for a highly sensitive label‐free detection of nucleic acids. Under proper oxidation conditions, the delicate nanostructure of PSi can be preserved, while providing sufficient dielectric insulation for application of high voltages. This enables the use of signal enhancement techniques, which are based on electric fields. Here, the DNA target molecules are focused using an electric field within a finite and confined zone, and this highly concentrated analyte is delivered to an on‐chip PSi Fabry–Pérot optical transducer, prefunctionalized with capture probes. Using reflective interferometric Fourier transform spectroscopy real‐time monitoring, a 1000‐fold improvement in limit of detection is demonstrated compared to a standard assay, using the same biosensor. Thus, a measured limit of detection of 1 × 10?9 m is achieved without compromising specificity. The concepts presented herein can be readily applied to other ionic targets, paving way for the development of other highly sensitive chemical and biochemical assays. 相似文献
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多孔硅的应用研究进展 总被引:1,自引:0,他引:1
多孔硅是一种新型的纳米半导体光电材料,室温下具有优异的光致发光、电致发光等特性,易与现有硅技术兼容,极有可能实现硅基光电器件等多个领域的应用.扼要论述了多孔硅在绝缘材料、敏感元件及传感器、照明材料及太阳能电池、光电器件以及作为合成其它材料的模板等多个领域内的应用进展情况,并对其发展前景作了展望。 相似文献
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