Research On MEMS Vector Hydrophone Based On Silicon Nanowires Design And Micro-nano Cross-scale Preparation

As one of the important components of underwater target detection,MEMS vector hydrophone has gradually become the key field of underwater acoustic detection research.MEMS vector hydrophones have many advantages,such as lighter weight,smaller volume,and stronger low-frequency detection capabilities.Vector hydrophone can not only detect underwater scalar information,but also detect vector information such as vibration velocity signal.Through the application of the vector hydrophone,we can obtain the information of the sound pressure of the target sound source and its orientation at the same time.After years of development,the ciliated bionic MEMS vector hydrophone has greatly optimized various performance indicators.However,there are still a series of problems with this type of MEMS vector hydrophone.It uses bonding to place the cilia,which has the problems of poor consistency and low alignment accuracy.These problems not only affect the performance of a single hydrophone,but also cause some difficulties in the application of hydrophone arrays.Based on the research background of MEMS vector underwater acoustic sensor and the development situation at home and abroad,this paper introduces the principle of bionic ciliated MEMS vector hydrophone.In principle,we proposed a micro-nano cross-scale integrated MEMS vector hydrophone structure,designed silicon nanowires as varistor units,and analyzed the nanowire giant piezoresistive model based on the surface depletion mechanism.At the same time,the integrated processing of silicon cilia and silicon dioxide beams were completed,and the integrated process design was completed.Various problems in the processing process were analyzed and researched,and the four beams of silicon dioxide,silicon cilia and silicon nanowires were prepared,and the verification of the entire process was finally achieved.Finally,the scanning electron microscope was used to observe and characterize the morphology.The test results show that the silica four beam and silicon cilia structure are formed,the beam thickness reaches 2 8).The value of the piezoresistance and piezoresistive characteristics of the MEMS hydrophone are tested using a probe station and a semiconductor analyzer.The value of the measured piezoresistance is about 12E3?.