Suspended Frame Structure with Phononic Crystals for Anchor Loss Reduction of MEMS Resonator

Abstract

In order for micro/nano-electro-mechanical systems (M/NEMS) resonators to make real impact to practical applications such as wireless communications and autonomous sensor networks, further improvements are needed in particular in the enhancement of quality factor $(Q)$. Herein, a novel geometry design with a suspended frame structure integrated with phononic crystals (PnC) unit cells was demonstrated to significantly reduce the anchor loss of ring-shaped thin-film piezoelectric-on-silicon bulk acoustic wave resonator and then enhance its $Q$. Finite-element-analysis (FEA) simulation was employed to systematically study the proposed design, which reveals that the $Q_{anc}$ of this novel geometry (i.e., R6T20FP-w5 with $Q_{anc}$ of 100000) achieved a maximum 83-fold enhancement compared with the pristine one (i.e., RNT10-w26 with $Q_{anc}$ is 1200).