Multi-Stage Frames for Q-Enhancement in Piezoelectric MEMS Resonators

Piezoelectric Micro-electro-mechanical systems (MEMS) resonators have attracted a wide range of interest due to their excellent properties. In this work, an Aluminum Nitride (AlN)-based MEMS resonator with multi-stage frames (MF) is proposed for quality factor (Q) enhancement, where the principle of MF is the effect of mechanical vibration isolation. Using finite element analysis (FEA) method, the proposed MF resonator has less acoustic energy leakage and higher Qanchor compared to the conventional resonators. Measurement results show that the MF resonator has a 1.74-fold unload-Q (Qu) enhancement compared to conventional resonators, suggesting less acoustic energy leakage into the substrates. The MF design is also suitable for high-frequency MEMS resonators with other piezoelectric materials such as Lithium Niobate or Lithium Tantalate.