关键词: MEMS加速度计, 封装优化, 有限元分析

Abstract: A high-temperature resistant MEMS accelerometer with a wider operating temperature range (-55-225 ℃) was developed by leveraging high-temperature SOI ASIC fabrication processes and micro-electromechanical system (MEMS) technology, thereby broadening the application scope of MEMS accelerometers. The temperature characteristics of MEMS accelerometers in high-temperature environments were also investigated. Stress was identified as the primary factor influencing the temperature coefficient of the accelerometer's zero bias. When excessive stress is applied, the MEMS accelerometer structure becomes deformed, resulting in excessive zero offset and temperature drift. Based on finite element analysis, the high-temperature accelerometer packaging was addressed first. The temperature performance of the MEMS accelerometer was improved through optimization of the packaging stress, and the zero bias variation over the entire temperature range was reduced to within 0.002 5g. The final high-temperature accelerometer was designed with a measurement range of ±50g, and a full-scale linearity better than 0.3%. These performance metrics are considered suitable for applications in complex high-temperature environments such as aerospace and oil drilling.

Key words: MEMS accelerometer, packaging optimization, finite element analysis