A₂-Mode Lamb Passive-Wireless Surface-Acoustic-Wave Micro-Pressure Sensor Based on Cantilever Beam Structure

Passive-wireless surface-acoustic-wave (SAW) micro-pressure sensors are suitable for extreme scenarios where wired sensors are not applicable. However, as the measured pressure decreases, conventional SAW micro-pressure sensors struggle to meet expected performance due to insufficient sensitivity. This article proposes a a method of using an (Formula presented.) -mode Lamb SAW sensor and introduces an inertial structure in the form of a cantilever beam to enhance sensitivity. An MEMS-compatible manufacturing process was employed to create a multi-layer structure of (Formula presented.), (Formula presented.), and (Formula presented.) for the SAW micro-pressure sensor. To investigate the operational performance of the SAW micro-pressure sensor, a micro-pressure testing system was established. The experimental results demonstrate that the sensor exhibits high sensitivity to micro-pressure, validating the effectiveness of the proposed design.