Laterally vibrating lithium niobate MEMS resonators with high electromechanical coupling and Quality factor

This paper reports on a new type of laterally vibrating micro-resonators (LVRs) enabled by ion sliced X-cut Lithium Niobate thin film and micro-machining. In operation, the device is excited into lateral vibrations, thus allowing the center frequency to be determined by the lithography-defined dimensions of the electrodes. This configuration enables monolithic multi-frequency solutions for future wireless communication. The designed devices have shown a high electromechanical coupling (k_t²) of 11% - the highest demonstrated for MEMS LVRs. Device orientation was also varied to investigate its impact on k_t² and experimental data has shown good agreement with theoretical predictions. The Quality factor of these devices has also shown a dependence on the orientation, ranging from 350 to 1100.