Quality Factor Enhancement of AlN-on-Si Lamb Wave Resonators Using a Hybrid of Phononic Crystal Shapes in Anchoring Boundaries

This paper describes the novel use of a hybrid phononic crystal (PnC) array formed by two PnC shapes on anchoring boundaries of a 7th harmonic Lamb wave aluminum nitride on silicon (AlN-on-Si) resonator. We demonstrate the effect of the hybrid PnC in boosting Q to the order 104. The hybrid PnC array comprises a disk PnC with a wide acoustic bandgap (ABG) and a ring PnC as an intermediary routing layer for input/output (I/O) electrical feeds to more effectively reduce anchor loss. We show that the wide ABG disk PnC provides 47dB of acoustic attenuation in a Lamb wave delay line.