Research On Characteristics Of Saw Pressure Sensor Based On ZnO Single Crystal

Sensor technology is a modern science and technology,with the rapid development of a high-tech,has attracted the attention of scholars from all walks of life.The surface acoustic wave pressure sensor owe great application prospects in the field of sensors due to the higher resolution and test accuracy,advanced production technology,suitable for mass production and other advantages.This paper first introduces the ZnO single crystal has the advantages of wide bandgap,high exciton binding energy and good electromechanical coupling properties.Therefore,it has very big advantage to apply ZnO single crystal to surface acoustic wave sensors.Secondly this paper introduces the theory and development history of surface acoustic wave and pressure sensors.Secondly,the ZnO single crystal surface acoustic wave resonator is modeled and simulated by the finite element analysis software COMSOL,with finite element analysis method.The 3D model of surface acoustic wave resonator is simplified to the 2D model,the symmetric and antimetric modes and BAW of SAW resonator are simulated,by analyzing the characteristics of resonant frequency of SAW devices,the phase velocity of ZnO single crystal is calculated as v=2670.169m/s.The conductance and displacement characteristics of single crystal ZnO-based surface acoustic wave resonators are studied.A ZnO single crystal SAW resonator consists of 5 IDTs and 5 Sound reflection gratings is designed and frequency response and displacement characteristics of this resonator are studied under with or without pressure loading.Frequency response of the SAW rensonator has a good negative linearrelationship with pressure load,the formula is y=162.0712-0.0149 x.The structure parameters of the devises are studied,including the height of the IDT,and metal coverage,as well as the thickness of the ZnO basement,which provide certain theoretical guidance for the preparation of SAW resonator.