Research On The Temperature Characteristic Of High Precision Micro-optical Accelerometer

MEMS accelerometers are very important sensors due to their small volume,low energy consumption,easy integration and so on.They are widely used in different fields,such as medical,inertial navigation,earthquake monitoring,automobile safety and so on.Traditional MEMS accelerometers are susceptible to electromagnetic interference and have low sensitivity,limiting their scope of application.MOEMS accelerometers,which integrate optical detection and MEMS technology,have the advantages of high measurement accuracy and less susceptibility to electromagnetic interference and have drawn wide attention.However,MOEMS accelerometers,like MEMS accelerometers,are also susceptible to temperature and therefore reduce their performance parameters.In this paper,the temperature performance of the MOEMS accelerometer has been analyzed in detail and experimentally tested,and the thermal stress of the optical detection unit was studied.A reasonable package structure was designed,which is expected to improve the temperature stability of the accelerometer.This paper introduced the working principle of micro-accelerometers,and summarized the research status of MEMS and MOEMS accelerometers as well as their respective advantages and disadvantages.At the same time,the current research status of the temperature characteristics of micro-accelerometers was introduced in detail.After that,the working principle of the MOEMS accelerometer based on grating interference was introduced.The temperature analysis and modeling of the micromechanical structure of the MOEMS accelerometer were carried out.The effects of temperature coefficient of elastic modulus and thermal expansion coefficient of silicon on the scale factor drift and zero drift of the accelerometer were analyzed in detail,paving the way for temperature compensation of the MOEMS accelerometer in the future.The experimental environment of the quasi-static temperature characteristic test was set up and the quasi-static temperature performance of the discrete MOEMS accelerometer system was tested and analyzed.According to the experimental results,it can be concluded that the system is more affected by the temperature when it is in the discrete state.According to the result of quasi-static temperature performance test,it was proposed to package the accelerometer's high-precision optical detection unit.The package thermal stress of the MOEMS accelerometer was analyzed from the material and dimensions of the package substrate and the adhesive using ANSYS finite element analysis software.Based on the analysis results,the micro-mechanical structure and grating were encapsulated with ceramic substrate and patch red glue,and the optical detection unit was simulated.The results showed that the influence of temperature on the package structure can be reduced to 6.4%,improving temperature stability of the accelerometer.Finally,a summary of the research was involved,and the prospects for the future work were proposed.