Investigation of bimaterial cantilever beam for heat sensing in liquid
Investigation of bimaterial cantilever beam for heat sensing in liquid
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DOI：
10.1016/j.sna.2015.11.030
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发表时间：
2016-05-01
影响因子：
4.6
通讯作者：
Toda, M.
中科院分区：
文献类型：
--
作者：
Voiculescu, I.;Liu, F.;Toda, M.
本文提出了理论和实验的温度分布沿着微悬臂梁在液体中工作，并在这项研究中用作温度传感器。这种悬臂梁的主要应用是用于传感哺乳动物细胞的温度变化。悬臂梁被微加工成由氮化硅和金薄层制成的复合结构。为了实现高灵敏度的悬臂梁被设想为具有微米尺度的长度和纳米尺度的厚度。由于氮化硅和金的热膨胀系数的不同值，非常小的温度变化产生的悬臂梁自由端的偏转。研究了悬臂梁式温度传感器在液体中工作时的温度标定问题。在本文中，使用微丝加热器作为局部热源，以产生校准目的所需的热量。将悬臂梁浸入液体中，加热器温度从27.5 ℃变化到71.8 ℃。与在离悬浮细胞一定距离处感测温度变化的情况类似，加热器位于离悬臂梁15 μ m处。将实验挠度值与理论挠度值进行了比较，并计算了系统的传热系数h。在低温下，传热系数值为381 W/m（2）K，在较高温度下为642 W/m（2）K。实验结果表明，当加热器位于悬臂梁中点附近时，悬臂梁的挠度最大。系统地研究悬臂梁在液体中的挠度随外加热的变化关系对于化学和生物学应用具有重要意义。(C)© 2016 Elsevier B. V.版权所有。
This paper presents the theoretical and experimental temperature profiles along a microcantilever beam operated in liquid and employed in this research as a temperature sensor. The main application of this cantilever beam is for sensing temperature variations of mammalian cells. The cantilever beam was microprocessed as a composite structure fabricated from thin layers of silicon nitride and gold. In order to achieve high sensitivity the cantilever beam was conceived with the length at microscale and the thickness at nanoscale dimensions. Very small temperature variations generated the deflection of the cantilever beam free end due to different values of the thermal expansion coefficients of silicon nitride and gold. The paper is focused on the temperature calibration of the cantilever beam temperature sensor when it is operated in liquid. In the paper a microwire heater was used as a localized heat source to generate the heat required for calibration purposes. The cantilever beam was immersed in the liquid and the heater temperature was varied from 27.5 degrees C to 71.8 degrees C. In analogy with the situation when temperature variations are sensed at certain distance from a cell in suspension the heater was located at 15 mu m distance from the cantilever beam. The experimental deflection values were compared with the theoretical deflection values and the heat transfer coefficient h of the system was calculated. At low temperatures the heat transfer coefficient value was 381 W/m(2)K and at higher temperatures 642 W/m(2)K. The experimental measurements illustrate that the cantilever beam deflection has the largest values when the heater was located near the midpoint of the cantilever beam. A systematic investigation of the cantilever beam deflection in liquid as a function of the applied heat is important for chemical and biological applications. (C) 2016 Elsevier B.V. All rights reserved.