擬側向電場聲波感測器之研究

Pseudo Lateral Field Excited Acoustic Wave Sensor

紀仲珉(Chung-min Chi)

指導教授 ： 陳永裕

大同大學/工程學院/機械工程學系所/碩士(2010年)

摘要

壓電聲波式感測器具有製程簡單與高靈敏度等優點，因此近年來已被廣泛地應用在生化感測領域。常見的壓電聲波式感測器包括石英晶體微天平（Quartz Crystal Microbalance, QCM）及側向電場（Lateral Field Excited, LFE）聲波感測器等，但QCM無法感測待測物的電性變化，而LFE無法於空氣中激振，因此本研究提出一創新壓電聲波式感測器，名為擬側向電場（Pseudo Lateral Field Excited Acoustic Wave Sensor, Pseudo-LFE）聲波感測器。首先利用有限元素法軟體COMSOL計算此感測器對各種感測標的之感測效能，也利用實驗量測來探討其對液體特性變化之靈敏度，並與QCM、LFE的靈敏度進行比較。結果顯示，Pseudo-LFE能穩定地在空氣中振盪，且具有較高的靈敏度，據此推論本研究所提出之Pseudo-LFE相當適合應用於各種待測物之量測。

關鍵字

擬側向電場聲波感測器 ； 有限元素法 ； 壓電聲波式感測器

並列摘要

In recent years, piezoelectric acoustic wave sensors, such as quartz crystal microbalance (QCM) and lateral field excited (LFE) acoustic wave sensor, have been widely investigated in biochemical sensing applications due to their high sensitivity and simple fabrication. However, the QCM is not capable of sensing surface electrical alteration, and the LFE sensor cannot be excited in air. Therefore, a novel piezoelectric acoustic wave sensor, namely pseudo lateral field excited (Pseudo-LFE) acoustic wave sensor, is proposed in this study. Finite element method and experiments were implemented to discuss sensitivities of the sensor to the characteristic variations of liquid or gas. The LFE sensor and QCM were also analyzed and measured for comparison. Results show that the Pseudo-LFE sensor successfully senses the mechanical and electrical variations of liquid or gas. Moreover, this sensor exhibits a higher sensitivity than the QCM and LFE sensor. According to the simulation and experimental results, we conclude that the Pseudo-LFE sensor is very suitable to apply in biochemical sensing.

並列關鍵字

Piezoelectric acoustic wave sensor ； Pseudo-LFE ； Finite element method

參考文獻

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