Shear mode resonators based on aluminum nitride round membranes with a ring-shaped electrode

We report a novel shear mode resonator excited by lateral field using an AlN/SiN membrane structure, for mass sensing applications. The shear acoustic wave was clearly observed using a ring-shaped electrode structure on a round membrane made of a very low stress (~ 50 MPa) and very thin (~ 970 nm) AlN film. A significant frequency shift (around 7 MHz) generated when dropping particles as loading masses on the surface of the devices, was measured, demonstrating the potential of these devices for mass sensing applications.