Design of T-shape vector hydrophone based on MEMS

This paper reports the design and fabrication of T-shape vector hydrophone based on MEMS inspired by fish lateral line. Based on the analysis of mechanical properties of T-beam, the design and fabrication process of microstructures with two different frequencies are described in detail, and the characteristics of the microstructures are analyzed by ANSYS. The first-order resonance frequencies of the two microstructures are 1970 Hz and 10 kHz, and the piezoresistors are placed away from edges about 120 μm. The T-beam microstructure is fabricated on silicon-on-insulator (SOI) wafers for uniform beam thickness. The test results showed that hydrophones have receiving sensitivity up to −180 dB and −192 dB at 1 kHz (0 dB = 1 V/μPa), and displayed a clear directivity pattern in the form of “8” shape.