Guided Sezawa Mode Phononic Racetrack Resonators in Scandium Aluminum Nitride on Silicon Carbide

Slow-On-fast piezoelectric platforms have facilitated the development of phononic integrated circuits (PnICs), establishing a foundation for high-performance integrated radio frequency signal processing systems with acoustic confinement, reduced loss, and wavelength-scale device architectures. Scandium aluminum nitride (ScAlN) on silicon carbide (SiC) has emerged as a popular PnIC platform due to its high electromechanical coupling, low loss and surface acoustic wave (SAW) mode confinement. This work presents a new device class to the PnIC component library by implementing traveling wave racetrack resonators in ScAlN on SiC. Add-Drop functionality is demonstrated in these devices, and the quality factors (Q) of the resonators is simultaneously characterized for the first time.