基于低温共烧陶瓷的微机械差分电容式加速度计的研究

低温共烧陶瓷（LTCC）技术是实现电子设备小型化、高密度集成化的主流封装/组装集成技术，可适用于耐高温、耐受恶劣环境下的特性要求。报道了以LTCC为结构材料设计、制作的一种MEMS差分电容式加速度计。该器件的敏感质量、4根悬臂梁结构都内嵌于LTCC多层基板，质量块和上下盖板之间通过印刷电极组成差分电容对；高精度电容检测芯片表贴于LTCC基板表面，将差分电容信号转化为电压信号。论文讨论了微机械LTCC加速度计的设计与制备、检测电路和性能测试。LTCC的高密度多层布线减小了互连线的长度和相关耦合寄生电容；基于集成芯片的检测电路解决了分立式检测电路的引起噪声大、电路复杂等问题。测试结果表明：该加速度计结构灵敏度较高，小载荷情况下表现出良好的线性关系，灵敏度约为30.3 mV/gn。

A Capacitive Micro-Accelerometer Based on LTCC Laminates

With the development of the miniaturization and high density integration of electronic devices,Low Tem?perature Co-fired Ceramic(LTCC)technology is becoming the mainstream technology for microelectronic and micro/nano multifunctional device packaging and assembly. This paper presents a capacitive micro-accelerometer embed?ded into LTCC packaging substrate. Its square shaped proof mass of the sensing element is suspended in the center by four folded beams which are connected to the frame. The design,simulation,fabrication,and performance test of the accelerometer are discussed. High density multilayer wiring supported by LTCC microfabrication reduces the length of the interconnect line between sensing elements and circuitry and the associated parasitic capacitance. The signal detecting circuit based on the integrated chip solves the problem of large noise,circuit complexity,and so on. The test results show that the accelerometer has sufficient sensitivity and good linear relationship at low overload and the sensitivity is about 30.3 mV/gn.