摘要
随着微机电系统（MEMS）技术的快速发展，电容式超声波传感器（CMUT）在医疗成像，无损检测等领域展现出巨大的潜力。振动薄膜作为CMUT的核心部件，其材料特征和几何参数决定了传感器的性能表现。本研究通过有限元仿真方法，系统性的分析了薄膜材料，几何构型及表面附加工艺对器件共振频率与最大位移的影响。仿真结果表明，Kapton薄膜相较于多晶硅薄膜，在相同几何尺寸下具有更低的共振频率和更大的位移响应，更适用于低频、高灵敏度应用场景。研究为面向不同应用需求的CMUT器件材料选择与结构优化提供了数据支撑与设计参考。
关键词： CMUT；柔性振动膜；Kapton；有限元仿真；共振频率
Abstract
With the rapid development of Micro-Electro-Mechanical Systems (MEMS) technology, Capacitive Micromachined Ultrasonic Transducers (CMUTs) have demonstrated significant potential in fields such as medical imaging and non-destructive testing. The vibrating membrane, as the core component of a CMUT, determines the performance of the device through its material properties and geometric parameters. In this study, a finite element simulation approach was employed to systematically analyze the effects of membrane material, geometric configuration, and surface additive processes on the resonant frequency and maximum displacement of the device. The simulation results indicate that, compared to polysilicon membranes, Kapton membranes exhibit lower resonant frequencies and larger displacement responses under the same geometric dimensions, making them more suitable for low-frequency, high-sensitivity application scenarios. This research provides data support and design references for material selection and structural optimization of CMUT devices tailored to different application requirements.
Key words： CMUT; Flexible vibrating diaphragm; Kapton; Finite element simulation; Resonant frequency
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