Research on Design Technology of Piezoelectric Hydrophone Based on Micro Additive Manufacturing

A piezoelectric MEMS hydrophone based on PZT-5h is proposed to solve the problem of poor low frequency response and low sensitivity of the hydrophone. Based on the technology of fabricating aluminum oxide ceramic elastic substrate with micro additive, and the hydrophone composed of PZT-5h piezoelectric sheet with 0.15 mm ultra-thin thickness, the elastic substrate structure of the hydrophone was optimized and designed, the elastic substrate structure was divided into sensitized structure and high-frequency structure. In this paper, the mechanical equation of the structure and the piezoelectric equation of the material are derived, the key factors affecting the sensitivity and low frequency response characteristics of the hydrophone are obtained, and the appropriate structural parameters are determined, and the simulation verification of the MEMS hydrophone design is carried out. The results show that the sensitivity of MEMS hydrophone is better than −191 dB in the frequency range of 0-5 kHz.