Wang Tao, Tang Zhengjie, Lin Huamao, Zhan Kun, Wan Jiang, Wu Shihao, Gu Yuandong, Luo Wenbo, Zhang Wanli
University of Electronic Science and Technology of China, School of Electronic Science and Engineering, Xiyuan Avenue, Chengdu 611731, China.
University of Electronic Science and Technology of China, State Key Laboratory of Electronic Thin Film and Integrated Devices, Xiyuan Avenue, Chengdu 611731, China.
Sensors (Basel). 2020 Mar 24;20(6):1788. doi: 10.3390/s20061788.
In this paper we demonstrate a novel acoustic wave pressure sensor, based on an aluminum nitride (AlN) piezoelectric thin film. It contains an integrated vacuum cavity, which is micro-fabricated using a cavity silicon-on-insulator (SOI) wafer. This sensor can directly measure the absolute pressure without the help of an external package, and the vacuum cavity gives the sensor a very accurate reference pressure. Meanwhile, the presented pressure sensor is superior to previously reported acoustic wave pressure sensors in terms of the temperature drift. With the carefully designed dual temperature compensation structure, a very low temperature coefficient of frequency (TCF) is achieved. Experimental results show the sensor can measure the absolute pressure in the range of 0 to 0.4 MPa, while the temperature range is from 20 °C to 220 °C with a TCF of -14.4 ppm/°C. Such a TCF is only about half of that of previously reported works.
在本文中，我们展示了一种基于氮化铝（AlN）压电薄膜的新型声波压力传感器。它包含一个集成真空腔，该真空腔是使用绝缘体上硅（SOI）晶圆通过微加工制造的。这种传感器无需外部封装即可直接测量绝对压力，并且真空腔为传感器提供了非常精确的参考压力。同时，所提出的压力传感器在温度漂移方面优于先前报道的声波压力传感器。通过精心设计的双温度补偿结构，实现了非常低的频率温度系数（TCF）。实验结果表明，该传感器能够测量0至0.4MPa范围内的绝对压力，温度范围为20°C至220°C，TCF为-14.4ppm/°C。这样的TCF仅约为先前报道工作的一半。
