电容式单质量三轴加速度计的研制

发布时间：2018-01-12 16:35

本文关键词：电容式单质量三轴加速度计的研制　出处：《苏州大学》2015年硕士论文　论文类型：学位论文

【摘要】：电容式加速度计广泛应用于国防、航空航天、汽车、通信等军用民用领域,是当前市场的主流和研究的热点。随着应用领域的不断扩大,单双轴电容式加速度计已无法满足使用的需求,三轴电容式加速度计集成成为重要的发展方向之一。本课题旨在研制一种基于单一敏感质量的三轴电容式加速度计,重点从电容式单质量三轴加速度计的结构设计、仿真优化和工艺制作三方面入手,研究提高器件灵敏度、降低非线性度、减小布朗噪声和交叉轴灵敏度的方法。本文首先针对平板电容的检测方法和结构进行分析研究,提出电容式单质量三轴加速度计的结构模型,分析其工作原理和耦合情况。基于力学法和能量法,建立弹性梁的理论模型,推导梁在器件工作模态的刚度公式。针对检测梳齿的工作原理进行分析,建立其等效模型。根据以上模型,理论计算电容式单质量三轴加速度计的各项性能参数。基于位移法和谐振频率法,运用有限元仿真软件,模拟验证梁在工作模态下刚度公式的准确性,并依此进行优化。模拟器件的工作模态,分析其灵敏度和许用应力情况。针对工艺和使用过程中热机械应力对器件性能的影响进行仿真分析,验证器件对应力的敏感程度。介绍电容式单质量三轴加速度计的引线层、中间连接层、结构层和pad层的版图绘制。采用基于表面硅工艺的多晶硅外延技术实现器件的加工制作。针对制作工艺对器件结构性能的影响进行分析,优化工艺流程。建立电容式单质量三轴加速度计的测试平台,对其性能指标进行测试分析。通过对比分析测试值和理论值的差异性,验证理论设计的正确性,同时验证电容式单质量三轴加速度计性能指标达到设计要求。
[Abstract]:Capacitive accelerometers are widely used in military and civil fields such as national defense, aerospace, automobile, communication and so on. Single and double axis capacitive accelerometers can no longer meet the needs of use. The integration of three-axis capacitive accelerometers has become one of the important development directions. The purpose of this paper is to develop a three-axis capacitive accelerometer based on single sensitive mass. Focusing on the capacitive single-mass three-axis accelerometer structure design, simulation optimization and processing three aspects, research to improve the device sensitivity and reduce the degree of nonlinearity. The method of reducing Brownian noise and cross-axis sensitivity. Firstly, the detection method and structure of plate capacitance are analyzed and studied, and the structure model of capacitive single-mass three-axis accelerometer is proposed. Based on the mechanical method and the energy method, the theoretical model of the elastic beam is established, and the stiffness formula of the beam working mode in the device is derived, and the working principle of detecting the comb tooth is analyzed. According to the above model, the performance parameters of capacitive single-mass three-axis accelerometer are calculated theoretically. Based on displacement method and resonant frequency method, finite element simulation software is used. The simulation verifies the accuracy of the stiffness formula of the beam in the working mode and optimizes the working mode of the device. The sensitivity and allowable stress are analyzed. The effect of thermo-mechanical stress on the performance of the device is simulated and analyzed. To verify the sensitivity of the device to stress. The lead layer and intermediate connection layer of capacitive single mass triaxial accelerometer are introduced. Structure layer and pad layer layout drawing. The polycrystalline silicon epitaxy technology based on surface silicon technology is used to realize the fabrication of the device. The effect of fabrication process on the structure and performance of the device is analyzed. Optimize the process flow. Establish the test platform of capacitive single-mass three-axis accelerometer, test and analyze its performance index. By comparing and analyzing the difference between the test value and the theoretical value, verify the correctness of the theoretical design. At the same time, the performance index of capacitive single-mass three-axis accelerometer is verified to meet the design requirements.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH824.4

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