Tilted $c$ -Axis Thin-Film Bulk Wave Resonant Pressure Sensors With Improved Sensitivity

Aluminum nitride thin-film bulk wave resonant pressure sensors employing c- and tilted c-axis texture, have been fabricated and tested for their pressure sensitivities. The c-axis tilted film bulk acoustic resonators pressure sensors demonstrate substantially higher-pressure sensitivity compared to its c-axis oriented counterpart. More specifically, the thickness plate quasi-shear resonance has demonstrated the highest pressure sensitivity while further being able to preserve its performance in liquid environment.