Development Of Differential Type MEMS Vector Hydrophone

According to the case that traditional vector hydrophone in practical application need auxiliary elastic suspension which has cause some trouble in engineering application, a kind of differential type MEMS vector hydrophone which could be used with rigid fix has been designed and fabricated, and the platform to test its performance has been built.At first, the research background and significance of vector hydrophone have been introduced, the development of it both in home and abroad has been concluded, and the drawbacks of it nowadays have been analyzed. A kind of MEMS vector hydrophone with low acceleration sensitivity has been designed, in light of the application environment and the acoustic propagation principle. The feasibility of this design has been verified simply by finite element simulation software. Secondly, a static mechanical model of the sensitive micro structure of MEMS vector hydrophone has been created, and the finite element statics analysis model has been established to verify the theoretical deduction results. Thirdly, on the basis of static mechanical model, a simplified calculation formula of the sensitive structure first modal frequency in water has been deduced and the formula has been verified by the finite element method. Then, combining the processing technology of outsourcing unit, the cross hydrophone MEMS layout and process flow has been designed, the processing of MEMS support structure has finished. The package for the hydrophone has been designed, the chip package and cilia integration has been complete, and the prototype of hydrophone has been made. At last, an experimental platform to test the prototype hydrophone has been built, and the test results are as following: the acoustic pressure sensitivity at 500 Hz is-185dB(0 dB reference value of 1V/μPa), acceleration sensitivity is-58dB(0d B reference value 1V/g). Above results show that this kind of differential MEMS vector hydrophone can meet the design requirements.