High Figure-of-Merit LiNbO3 Lamb Wave Resonators Implemented by Two-Dimensional Bulk Reflector Arrays

This work demonstrates a figure-of-merit (FOM) enhancement technology for the first asymmetric lamb wave resonator (LWR) based on a Z-cut lithium niobate (LN) thin film. Two-Dimensional reflector arrays are formed in the piezoelectric layer to prevent energy leakage. The fabricated LWR achieves an operating frequency of around 6 GHz and an effective electromechanical coefficient $\left( {k_{eff}^2} \right)$ of 26%. The LWR with reflector arrays possesses a FOM of 360, an improvement of 396% over that of LWRs without reflectors, which is consistent with the simulation results.