基于压电器件的屋顶瓦状模式的几何研究在 AlN 压电微悬臂梁作为粘度-密度传感器中的应用。

A Geometrical Study on the Roof Tile-Shaped Modes in AlN-Based Piezoelectric Microcantilevers as Viscosity⁻Density Sensors.

机构信息

Microsystems, Actuators and Sensors Group, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain.

Electronic Engineering Department, Hijjawi Faculty for Engineering Technology, Yarmouk University, 21163 Irbid, Jordan.

出版信息

Sensors (Basel). 2019 Feb 6;19(3):658. doi: 10.3390/s19030658.

DOI:10.3390/s19030658

PMID:30736296

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6387016/

Abstract

Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 µm and thicknesses between 10 and 60 µm is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 × 900 × 10 µm³ cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10 g/mL and 10 mPa·s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.

摘要

基于瓦片模态的悬梁谐振器最近已经证明了其适用于液体介质监测应用。早期的研究表明，模态的某些尺寸和阶数的组合可以最大化 Q 因子，这可能表明存在两种具有不同几何依赖性的损耗机制之间的竞争。为了提供更深入的了解，对长度和宽度在 250 到 3000 µm 之间，厚度在 10 到 60 µm 之间的微悬臂谐振器中的这些模态的 Q 因子和共振频率进行了全面研究。这些模态可以通过薄的压电 AlN 薄膜和适当设计的顶部电极布局来有效地激发。在液体介质中对谐振器进行了电气和光学特性分析，然后根据质量因子和共振频率来评估其性能。在异丙醇中，对于在 4 MHz 下以第 11 阶瓦片模态振动的 1000×900×10 µm³的悬臂梁，测量到高达 140 的 Q 因子；对于几何优化的低于 1 MHz 共振的悬臂梁，估计密度和粘度分辨率分别为 10 g/mL 和 10 mPa·s。