Spurious mode suppression piezoelectric resonator design

摘要

Provided are methods and apparatus to improve upon conventional piezoelectric resonators. Also provided are apparatus and methods to improve upon filters having piezoelectric resonators. In an example a piezoelectric resonator includes a substrate and a piezoelectric material disposed on the substrate. A first electrode and a second electrode are disposed on the piezoelectric material. The piezoelectric resonator has a passband and a portion of the perimeter of the piezoelectric material is anchored to the substrate to suppress an in band spurious mode of the piezoelectric material. The portion if unanchored would exhibit maximum near maximum and/or excessive displacement deflection at resonance. The piezoelectric resonator can be integrated in a semiconductor die. Multiple filters having piezoelectric resonators with respective different passbands can be disposed on the substrate.