碳化硅MEMS压阻式压力传感器的结构设计及性能研究

Structural Design and Performance Research of Silicon Carbide MEMS Piezoresistive Pressure Sensor

摘要: 基于MEMS技术的硅基压力传感器因其体积小和精度高被广泛应用于多个领域。然而，由于其固有材料属性的限制，硅基传感器不适用于高压环境。为此，本文提出了一种半岛–杆梁结构的碳化硅MEMS压阻式压力传感器，通过在膜片表面加工半岛和杆梁结构，可以增加感压膜片局部刚度，提高传感器的整体性能。基于小挠度理论，结合数学建模和仿真分析，比较了传统圆形结构膜片和半岛–杆梁结构膜片的输出性能。结果表明，所提出的半岛–杆梁结构传感器在0~10 MPa的压力范围内可以实现2.19 mV/V/MPa的灵敏度，比传统圆形结构灵敏度提高了58.69%。通过设计新的膜片结构，传感器的线性度和灵敏度得到了有效的改善，为压阻式压力传感器在极端环境下的正常工作奠定了基础。

Abstract: Silicon-based pressure sensors based on MEMS technology are widely used in multiple fields due to their small size and high precision. However, due to the limitations of their inherent material properties, silicon-based sensors are not suitable for high-pressure environments. For this purpose, this paper proposes a peninsula-rod beam structure silicon carbide MEMS piezoresistive pressure sensor. By processing the peninsula and rod beam structure on the diaphragm surface, the local stiffness of the pressure-sensing diaphragm can be increased, and the overall performance of the sensor can be improved. Based on the small deflection theory, combined with mathematical modeling and simulation analysis, the output performance of the traditional circular structure diaphragm and the peninsula - rod beam structure diaphragm was compared. The results show that the proposed peninsula - rod beam structure sensor can achieve a sensitivity of 2.19 mV/V/MPa within the pressure range of 0~10 MPa, which is 58.69% higher than that of the traditional circular structure. By designing a new diaphragm structure, the linearity and sensitivity of the sensor have been effectively improved, laying a foundation for the normal operation of piezoresistive pressure sensors in extreme environments.