Design of ciliated MEMS vector hydrophone based on stainless steel mesh cap

Abstract The polyurethane-encapsulated lateral line-inspired MEMS vector hydrophone has problems such as low-frequency sensitivity (10–80 Hz) loss and narrow working bandwidth. In order to eliminate these two problems, a new encapsulation with a stainless steel mesh cap structure was proposed. This paper first verified the sensitivity loss and narrow working bandwidth of the polyurethane encapsulation through experiments and simulations, analyzed the impact of the perforation rate, thickness, and aperture of the stainless steel mesh cap structure on the vector hydrophone through simulation, and finally made 8 types of stainless steel mesh cap with different apertures was tested experimentally. Finally, the experimental results show that the sensitivity of the stainless steel mesh encapsulation in the low frequency range (10–80 Hz) is improved by an average of 12 dB than that of the polyurethane encapsulation, and the working bandwidth has been increased from 10–210 Hz to 10–667 Hz.