热电堆式MEMS气体流量传感器设计及性能研究

Design and Performance Study of Thermopile-based MEMS Gas Flow Sensor

提出一种由微加热器和热电堆构成的热式MEMS气体流量传感器用以实现高灵敏、快响应且低功耗的气体流量检测。采用N/P型重掺杂多晶硅材料构造双层堆叠的热电堆结构,可以实现低热导和高塞贝克系数,具有更高的温度敏感性。实验测试表明,该传感器件在0~1000 sccm的气流范围内灵敏度可达0.309 mV/sccm(58.22 mV/ms-1),响应时间仅约139 ms,其工作电压为2.56 V时,微加热器的加热功耗仅有34.9 mW。该器件的整体尺寸仅有1300 mm×1300 mm,有利于检测系统的小型化和集成化,在动力氢燃料电池、医疗辅助呼吸设备等流速流量检测场景中具有一定应用价值。

A thermal MEMS gas flow sensor consisting of a microheater and a thermopile is proposed to achieve highly sensi⁃tive,fast response and low power consumption for gas flow measurement.The thermopile structure uses N/P type heavily doped poly⁃silicon to construct a double stacked structure,which can achieve low thermal conductivity and high seeebeck coefficient with high⁃er temperature sensitivity.Experimental tests show that the sensor device has a sensitivity of 0.309 mV/sccm(i.e.,58.22 mV/ms^(-1))in the airflow range of 0~1000 sccm,a response time of only about 139 ms,and a microheater heating power consumption of only 34.9 mW at an operating voltage of 2.56 V.The overall size of the sensor is only 1300 mm×1300 mm,which is conducive to the min⁃iaturization and integration of the detection system.Application value in flow rate flow detection scenarios such as ship and land vehi⁃cle powered hydrogen fuel cells,medical assisted breathing equipment.