Structural Design And Process Study Of Micro Hemispherical Resonator Gyroscope

With the development of MEMS technology,the large number of navigation devices is applied to civilian equipment and miniaturization needs,as well as the traditional hemisphere resonant gyroscope itself demonstrated by the unique advantages,which are making the micro-hemisphere resonant gyroscope(pHRG)has become one of the hot spots in the field of MEMS sensors.In this paper,there are two methods to improve the quality factor(O)of ?HRG,one of to low the frequency splits and another of reducing the energy loss of ?HRG,which lays the foundation for the design of ?HRG with the high quality factor.Firstly,the research background and development of ?HRG are introduced in detail,which provides a reference for the modeling and processing of micro-hemisphere harmonic resonator.The design of micro-hemisphere resonant gyroscope is broadened.Secondly,the modeling approaches of ?HRG are compared.The dynamic characteristics and resonant frequencies of pHRG are analyzed by using the mathematical model based on the Kirchhoff hemispherical resonator.The frequency splits caused the fourth harmonic of density and elastic modulus inhomogeneity of the shell material and nonuniform radius of shell is researched,which provides theoretical guidance for reducing the frequency splits.Thirdly,the various energy loss mechanisms of pHRG are analyzed.The relationship between the quality factor and the energy loss is introduced.The thermoelastic damping,thermoelastic damping,support loss,and squeeze film damping of the microsphere resonator with different structural were simulated by using COMSOL software.These results of simulation provide the basis for reducing the energy loss of pHRG.Fourthly,the simulation of model and harmonic response is performed by ANSYS software to predict the natural frequency and frequency splits of four common spherical shell structures.Then,the structural and material error is simulated to know their influence on the frequency splits.Finally,micro-hemispherical resonator is designed.Finally,the fabrication process of the micro-hemisphere resonator is introduced and compared.On the basis,an assembled ?HRG based on SOI package is proposed.The fabrication processes are described in detail.Using HNA solution wet etching and SF6 dry etching hemispherical shell mold is performed for the preliminary test.