A Laterally Excited Bulk Acoustic Wave Resonator towards High Figure-of-Merit in Radio-Frequency Applications

This work presents a figure-of-merit (FOM) enhancement technique of laterally excited bulk acoustic resonator (XBAR) based on Z-cut Lithium Niobate thin film. The proposed energy-focused electrode configuration of XBAR can concentrate the acoustic energy in the center of resonator reducing the energy dissipation and improve the FOM efficiently. The fabricated resonator achieves a resonant frequency of 5 GHz, a high electromechanical coefficient of 20.54%, an outstanding FOM of 100.24 as well as spurious mode free in a wide band, showing a potential for 5G filter applications.