用于矢量水听器的应力集中MEMS敏感单元仿真研究  

Simulation analysis of stress concentrated MEMS sensitive unit for vector hydrophones

作　　者：肖邦 赵荣荣[1,2] 殷忆昕 XIAO Bang;ZHAO Rongrong;YIN Yixin(Shanghai Marine Electronic Equipment Research Institute,Shanghai 201108,China;National Key Laboratory of Science and Technology on Underwater Acoustic Antagonizing,Shanghai 201108,China)

机构地区：[1]上海船舶电子设备研究所,上海201108 [2]水声对抗技术重点实验室,上海201108

出　　处：《声学技术》2025年第2期302-308,共7页Technical Acoustics

摘　　要：敏感单元作为同振式矢量水听器的核心元件,其小型化将有助于水听器整体体积和质量的减小。采用微机电系统(micro-electro-mechanicalsystem,MEMS)结构是实现敏感单元小型化的有效途径。文章针对一种应力集中的MEMS敏感单元进行仿真研究。在质量块-梯形悬臂梁结构基础上,将单梯形悬臂梁改进为双梯形悬臂梁。同时,在悬臂梁近固定端处厚度方向刻蚀凹槽,进一步提高梁上压电层的局部应力。通过有限元仿真,对比三种不同结构敏感单元对应矢量水听器模型的灵敏度频域响应性能,并从梁上应力分布角度对性能差异进行分析。研究发现,相较于单梯形梁,双梯形悬臂梁结构水听器灵敏度提升7.7 dB。此外,增加悬臂梁厚度且在悬臂梁根部刻蚀凹槽,使得对应水听器灵敏度和带宽均得到改善。悬臂梁厚度为80μm、根部凹槽深度为40μm、宽度为100μm的双梯形悬臂梁对应矢量水听器的谐振频率为1496.8 Hz,在频率为630 Hz、参考值为1 V·(μPa)-1时,灵敏度为-210.8 dB。Sensitive unit is the key component of the co-vibration vector hydrophones,and its miniaturization helps reduce the overall volume and mass of the hydrophone.Simulation research on the MEMS sensitive unit with stress concentration is conducted in this article.Based on a mass block trapezoidal cantilever beam structure,a single trapezoidal cantilever beam is transformed into a double trapezoidal cantilever beam.Moreover,grooves are etched in the thickness direction near the fixed end of the cantilever beam,further increasing the local stress of the piezoelectric layer of the beam.Sensitivity frequency responses of three different structural cantilever beam models for vector hydrophones are compared by finite element simulation.and performance differences from perspectives of stress distribution on beams are analyzed.It is found that the double trapezoidal cantilever beam structure enhanced hydrophone sensitivity by 7.7 dB than that of single trapezoidal beam.Additionally,increasing thickness of the cantilever beam and etching grooves at its root,will improve the sensitivity and bandwidth for vector hydrophones.The resonant frequency of 80μm thickness double trapezoidal cantilever beam with a root groove of 40μm depth and 100μm width is 1496.8 Hz.At the frequency of 630 Hz and the reference value of 1 V·(μPa)-1,the sensitivity is-210.8 dB.

关 键 词：矢量水听器 敏感单元 悬臂梁 应力集中 仿真分析 微机电系统 

分 类 号：TB565.1[交通运输工程—水声工程]