X-Cut Lithium Niobate Laterally Vibrating MEMS Resonator With Figure of Merit of 1560

This letter reports on the design, fabrication, and testing of an X-cut lithium niobate laterally vibrating resonator operating around 50 MHz and exhibiting a record figure of merit–FoM = product of electromechanical coupling (kₜ²) and quality factor at a resonance (Qₛ)–of 1560. For practical applications, the individual resonator is arranged in a large array so as to achieve a static capacitance around 1 pF, while still preserving a high FoM of 570. Modeling of anchor losses through finite element analysis is used to guide the design of these resonators, which simultaneously exhibit high electromechanical coupling (kₜ² > 30%) and high quality factor (Qₛ > 5000) in vacuum.l [2018-0097]