An One-port A2 Mode AlN Lamb Wave Resonator Based on SOI Substrate

In this paper, we propose an one-port A1N lamb wave resonator utilizing the second-order asymmetric (A2) mode based on a silicon-on-insulator (SOI) substrate. Heavily doped silicon is chosen as the bottom layer, while a vertically arranged double-electrodes design is utilized to compensate for the effective electromechanical coupling coefficient ($\mathrm{k}_{\mathrm{t}^{2}}$). Finite element analysis (FEA) is used to investigate the resonance mode. After microfabrication and electrical characterization, the Butterworth-van Dyke (BVD) model is used to fit the measured admittance curve to obtain resonance performance. The characterization results show that a $\mathrm{k}_{\mathrm{t}^{2}}$ of 0.063% and a Q of 522.4 are achieved at a resonant frequency of 774MHz, reporting a high phase velocity exceeding 75000m/s.