10–60-GHz Electromechanical Resonators Using Thin-Film Lithium Niobate

This work presents a new class of microelectromechanical system (MEMS) resonator toward 60 GHz for the fifth-generation (5G) wireless communications. The wide range of the operating frequencies is achieved by resorting to different orders of the antisymmetric Lamb wave modes in a 400-nm-thick Z-cut lithium niobate thin film. The resonance of 55 GHz demonstrated in this work marks the highest operating frequency for piezoelectric electromechanical devices. The fabricated device shows an extracted mechanical Q of 340 and an f x Q product of 1.87 × 10
¹³
in a footprint of 2 × 10
^-3
mm
²
. The performance has shown the strong potential of LiNbO
₃
antisymmetric mode devices for front-end applications in 5G high-band.