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利用等厚干涉法测量了棱镜—薄膜耦合器的耦合间隙,在不同耦合间隙下测量了薄膜波导模式的传播常数、薄膜折射率和薄膜厚度。用 Tien 和 Urich 有关棱镜—薄膜耦合器的理论分析了耦合间隙对薄膜参数测量误差的影响。 相似文献
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纳米金属薄膜厚度的无损测量是薄膜设计和制备 的关键技术,对非贵金属薄膜厚度 的测量尤为困难。本文首次提出用中红外3.39 μm激光波长并设计棱 镜—匹配液—待测金属 薄膜—玻璃衬底结构来激发长程表面等离子波。计算了长程表面等离子波的衰减全反射和表 面等离子共振吸收峰的半宽度,结果表明长程表面等离子波半宽度只有表面等离波的4.7%, 可以有效提高测量的灵敏度。通过实验测量表明:衰减全反射吸收峰的最小值在10 nm厚 度范围内测量曲线显示了较好的线性,铁薄膜厚度的测量范围为10 -90 nm,测量分辨率可 达到1nm。研究发现通过改变匹配液厚度和折射率,还可以用来测量其它非贵金属薄膜厚度 ,大大拓展了该测量方法应用范围,为非贵金属薄膜厚度的测量提供了一种全新的技术检测 线路。 相似文献
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基于偏振光反射多点法测量薄膜参数 总被引:1,自引:2,他引:1
依据偏振光反射原理和多角度测量的多点拟合算法,实现了对薄膜材料折射率和厚度的精确测量。将高准直半导体激光入射到薄膜样品与空气分界面上,逐步旋转样品或改变样品表面的入射角,得到待测样品的反射率随入射角变化曲线。在曲线上取不同入射角处所对应的反射率,根据计算公式求解出多组薄膜厚度和折射率。利用已测量的多组反射率与求解出的薄膜参数相应反射率拟合后可确定出薄膜参数最优解。在求出的薄膜参数附近拓展一定范围再次拟合,可求出更精确的薄膜参数。基于此方法测量了SiO2薄膜的折射率和厚度,测量折射率误差不超过0.3%,厚度误差不超过0.07%。 相似文献
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在应用压电薄膜测量结构表面应变时,薄膜上的感应电压是其面内两个正交方向应变的函数。要获得结构表面某处一个方向的应变,就必须在该处粘贴和检测两片以上的压电薄膜,这对应用于随机载荷作用下的结构应变测量非常不便。利用压电薄膜材料的各向异性开发了组合式压电薄膜应变传感器,这使检测的感应电压和结构表面单一方向的应变成正比关系。根据压电方程推导了组合式压电薄膜输出电压和被测单向应变间的关系,并通过对一个带有小孔平板试件的应变分布测量试验和有限元数值分析,验证了该组合式应变传感器的可行性及具有很高的测量精度。该法操作简单,对实际工程结构应变测量具有重要的实用价值。 相似文献
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用化学溶液沉积法分别在Si(100)和石英玻璃衬底上成功制备了一系列Bi4-xLaxTi3O12(BLT)铁电薄膜;用X-射线衍射仪测量了不同退火温度和不同掺镧量的BLT薄膜的结晶情况,结果显示随着退火温度的升高BLT薄膜结晶越来越好,镧的掺入并不改变钛酸铋薄膜的钙钛矿结构;用椭偏光谱仪对不同退火温度的BLT薄膜进行了椭偏光谱测量,分析得到了薄膜的光学常数谱;用激光显微拉曼光谱仪对不同掺镧量的BLT薄膜进行激光拉曼谱测量,得到了BLT薄膜振动模式随掺镧量的变化. 相似文献
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报道了一种测量聚合物薄膜电光系数的简单方法。这种方法是用石英晶体的逆压电效应补偿聚合物薄膜电光效应引起的光程变化,测量聚合物薄膜电光系数相对于石英晶体压电常数d11的大小,这种方法可以用来测量所有光学薄膜的电光系数。文章介绍了采用此方法测量几种新的聚合物薄膜的电光系数。 相似文献
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基于宏电极的单频皮肤阻抗测量是利用阻抗进行皮肤渗透性研究的传统方法之一,其存在误差大、灵敏度低且不易于设备集成的缺点。由此,该文通过分析皮肤的分层生理结构以及皮肤渗透性与角质层(SC)阻抗的关系,设计了基于柔性非对称叉指微电极的皮肤阻抗传感器,构建了RCW分层阻抗模型,实现了对人体角质层阻抗的检测分析。实验结果表明,传感器输出的阻抗模值 和 模型拟合参数可用作表征皮肤渗透性的重要指标。该方法可用于区分不同个体的皮肤渗透性,为人体生理生化检测相关的可穿戴设备参数调节提供依据。 相似文献
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In this paper, a broad-band characterization method for measuring the complex permeability tensor components and complex scalar permittivity of magnetized ferrites is described. The technique is based on the reflection/transmission measurement of a rectangular waveguide partly filled with the ferrite that is to be characterized. The fundamental principle of the measurement consists in using the anisotropy of the material to lead to the nonreciprocity of the device in order to have the same number of measurable parameters (the S-parameters of the cell) for the characteristics we want to determine. Here, we will recall the principle of the mode-matching method used for the electromagnetic analysis of the cell (direct problem). We will bring to the fore the difficulties linked to the determination of the complex propagation constants of the different modes and will present a calculation procedure that makes this determination in a wide-frequency range easier. We will then compare at X-band frequencies (8-12 GHz) the theoretical S-parameters with those measured for ferrites of well-known properties in order to validate the direct problem. The determination of the permittivity and permeability values from the measured parameters (inverse problem) is not addressed here 相似文献
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S. N. Starostenko K. N. Rozanov 《Journal of Communications Technology and Electronics》2013,58(11):1076-1084
It is shown that the accuracy of measurement of the microwave permeability of thin films in a short-circuited strip cell can be substantially enhanced through taking into account the S parameters of the interior irregularities of the cell with the use of a calibration procedure involving two mutually supplementing reference samples. One of the reference samples is chosen to be a composite ferromagnet with the known frequency dependence of the constitutive parameters, and the other can be a nonmagnetic metal strip. For small samples with a low magnetic susceptibility, the measurement error can be 10–20 times reduced as compared to standard methods. In addition, the effect of the permittivity on the measured value of the magnetic susceptibility is taken into account. The method is tested for measurements of the permeability of prototypes and can be applied to calibrate other nondemountable partly filledtransmission lines. 相似文献
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This paper proposes a new method for the swept-frequency measurement of a solid material's complex permittivity and complex permeability. The proposed method utilizes a columnar specimen inserted in a rectangular waveguide, and the two-port S-parameters of the specimen are measured. In the analysis, the S-parameters are rigorously formulated in which the waveguide's fundamental mode, as well as the higher order modes are taken into account. Measurement was performed by using a standard waveguide and three types of materials as specimens. Results were compared with the conventional transmission-line method using the same rectangular waveguide. It is confirmed that the complex permittivity and complex permeability measured by the proposed method agrees very well with those measured by the conventional transmission-line method. 相似文献
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