Piezoelectric micromachined ultrasonic transducers: Modeling the influence of structural parameters on device performance
Piezoelectric micromachined ultrasonic transducers: Modeling the influence of structural parameters on device performance
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DOI：
10.1109/tuffc.2005.1417268
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发表时间：
2005-03-01
影响因子：
3.6
通讯作者：
Bandyopadhyay, A
中科院分区：
文献类型：
--
作者：
Akasheh, F;Fraser, JD;Bandyopadhyay, A
压电微机械超声换能器（pMUT），传统的一维相控阵超声换能器的潜在替代品，进行了研究。我们使用建模方法来研究锆钛酸铅（PZT）驱动的pMUT的性能为2-10 MHz的频率范围内，优化最大耦合系数，作为设备设计的函数。使用为此目的而设计的原始工具，开发了一个全面的构建测试有限元模型来预测和测量器件性能。特别是，该模型估计的设备耦合系数和声阻抗，除了容易提取的谐振频率和带宽。为了验证该模型，原型装置的建立和测试，显示出良好的模型预测和实验结果之间的协议。模拟结果表明，硅膜，PZT，和顶部电极的厚度以及顶部电极设计的耦合系数显着影响。结果还表明，在最大化耦合系数同时将设备声阻抗保持在与人体相匹配的水平方面具有相当大的灵活性。带宽被证明是优于传统的传感器，在某些情况下，达到102%的上级。
Piezoelectric micromachined ultrasonic transducers (pMUTs), a potential alternative for conventional one-dimensional phased array ultrasonic transducers, were investigated. We used a modeling approach to study the performance of lead zirconate titanate (PZT)-driven pMUTs for the frequency range of 2-10 MHz, optimized for maximum coupling coefficient, as a function of device design. Using original tools designed for the purpose, a comprehensive build-test finite element model was developed to predict and measure the device performance. In particular, the model estimates the device coupling coefficient and the acoustic impedance, besides the readily extractable resonance frequency and bandwidth. To validate the model, a prototype device was built and tested, showing good agreement between the model predictions and experimental results. Modeling results indicate that the coupling coefficient is significantly affected by silicon membrane, PZT, and top electrode thickness as well as the top electrode design. Results also indicate considerable flexibility in maximizing the coupling coefficient while maintaining the device acoustic impedance at a level matching that of the human body. The bandwidth proved to be superior to that of conventional transducers, reaching 102% in some cases.