Related Experiment Video
Updated: Nov 26, 2025

Sensitivity Enhancement of Soft Capacitive Pressure Sensors Using a Solvent Evaporation-Based Porosity Control Technique
Published on: March 24, 2023
A Low Temperature Drifting Acoustic Wave Pressure Sensor with an Integrated Vacuum Cavity for Absolute Pressure
Tao Wang1,2,3, Zhengjie Tang1,2,3, Huamao Lin3
1University of Electronic Science and Technology of China, School of Electronic Science and Engineering, Xiyuan Avenue, Chengdu 611731, China.
Abstract:
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.
Related Concept Videos
Measurement of Fluid Pressure
A basic form of manometer is the piezometer, a vertical tube open at the top and filled with the same...
Pressure Gauges
Sound as Pressure Waves
The pressure fluctuation depends on the difference in displacements between the successive points in the...
Constant Pressure Calorimetry
Pressure Variation in a Fluid at Rest
When measuring pressure at two different levels within the fluid, the difference in...
Vapor Pressure of Fluid
When a liquid is placed in a closed container with a small air space, and the space is evacuated, vapor molecules will...

