Comparison between different MEMS Laterally Vibrating Resonator Technologies for Passive Voltage Amplification in an RF Front-End System

This paper describes the challenges associated with attaining passive voltage gain by means of piezoelectric MEMS Laterally Vibrating Resonators (LVRs) in an RF frontend (RFFE) system. LVR technologies based on different piezoelectric films - Aluminum Nitride (AlN), Scandium-doped Aluminum Nitride (Sc
_x
Al
_1-x
N), and Y-cut and X-cut Lithium Niobate (LN) - are compared in regards to their impact on the sensitivity of an ultra-low power wake-up resonant micromechanical receiver (RMR) [1]. Due to the outstanding performance in terms of quality factor at resonance (Q
_s
) and electromechanical coupling (k
_t
²
), X-cut Lithium Niobate resonators are identified as the optimal approach for this radio architecture. Design, fabrication, and testing of an array of X-cut LN resonators is finally presented to demonstrate the capabilities of this technology.