A Lamb Wave Resonator with Trapezoidal Interdigitated Electrodes

Due to its multimodal characteristics, filters composed of aluminum nitride-based Lamb wave resonators are easily susceptible to interference from spurious modes. This paper constructed trapezoidal interdigitated electrodes based on modal vibration patterns and dispersion characteristics, and verified their suppression effect on spurious modes through simulation software (COMSOL Multiphysics 5.6). Finally, through process fabrication, we achieved a spurious-free S1 mode resonator, with the effective electromechanical coupling coefficient of 3.79
^%
and resonance at 2.583GHz.