| With the continuous expansion of the application field of MEMS gyroscopes,the demand for high-performance MEMS gyroscopes with higher quality factors and better temperature stability has become more urgent.Fused silica is an insulator with excellent thermal conductivity and thermal expansion coefficient.Compared with silicon-based MEMS gyroscopes,it can greatly reduce parasitic effects,enhance temperature stability and improve quality factor,and has broad development potential.However,the current processing technology on the micro-scale structure of fused silica is only suitable for the fields of optics,biology,microfluidics et al.In the field of MEMS,especially the processing technology of the planar resonant structure is still immature and cannot match the processing level of silicon-based inertial devices.In response to the above problems,this thesis mainly focuses on the research on the processing technology of fused silica material,and takes the sensitive structure of the butterfly gyroscope as the object.Considering the machining characteristics of resonant structure with key size of micrometer and the difficult machining properties of fused silica material,the two processing techniques of femtosecond laser processing and dry etching were studied,and higher precision processing results were obtained.Considering the existing technology level,a high-efficiency technology plan based on femtosecond laser was developed,the prototype of the fused silica gyroscope was prepared,and the processing error was characterized and analyzed.The final test results show that the quality factor of the fused silica butterfly gyroscope is about 10 times higher than that of the silicon-based butterfly gyroscope.It has achieved an order of magnitude improvement,which effectively proves the material advantages of fused silica,and provides a certain reference for the subsequent development of micro-inertial devices based on fused silica materials. |
