The investigation of integrated SAW strain sensor based on AlN/TC4 structure

Authors：Shu, Lin^*; Wang, Xuemin; Li, Ling; Yan, Dawei; Peng, Liping; Fan, Long; Wu, Weidong

Source：Sensors and Actuators, A: Physical , 2019, 293: 14-20.

DOI：10.1016/j.sna.2019.04.012

• Surface acoustic wave
• Integrated sensor
• Strain
• Aluminum nitride
• Metal substrate

This paper reports a novel strain sensor integrated on metal component. High-performance SAW strain sensor is embed on the layered AlN/TC4(Ti-6Al-4 V) structure by lift-off photolithography techniques, while the AlN film is directly deposited on the TC4 metal beam without bonding materials. The strain characteristics of the integrated sensor have been simulated and experimental investigated. The finite element modeling (FEM) simulation reveals that the strain transfer ratio (STR) of the sensor reaches 0.992 at 20 degrees C. The experimental results show that the strain sensitivity of the sensor reaches 1.61 ppm/mu epsilon with a deviation of 0.56%. The strain hysteresis error of the SAW devices is about 0.32% at 25 degrees C. The temperature behavior in strain sensitivity and hysteresis errors have also been studied. Though negative effects caused by increasing of operation temperature on its strain response, the integrated SAW sensor shows better performance than the reported one in a wide range of operation temperature. The prepared layered SAW sensor integrated with TC4 alloy has great potential applications in high temperature harsh environment.

• Institution
  中国工程物理研究院; 电子科技大学; 中国工程物理研究院激光聚变研究中心