The piezoelectric properties of the Ill-N materials system are ideal for MEMS acoustic resonators. Because of the small size of these resonators, there is potential for on-chip integration with other GaN-based devices such as high-electron-mobility transistors. We are interested in understanding how resonator design affects resonator performance at high frequencies through physics-based modeling. Extensive facilities are available in-house for materials growth and characterization, device modeling, device fabrication, and electrical testing.