Affiliations: [a] Piezoelectric Device Laboratory, School of Mechanical Engineering and Mechanics, Ningbo University, Ningbo, Zhejiang 315211, China | [b] School of Mechanical and Electrical Engineering, Ningbo Dahongying University, Ningbo, Zhejiang 315175, China | [c] Department of Mechanical and Materials Engineering, the University of Nebraska-Lincoln, Lincoln, NE 68588-0526, USA
Correspondence:
[*]
Corresponding author: Jiashi Yang, Piezoelectric Device Laboratory, School of Mechanical Engineering and Mechanics, Ningbo University, Ningbo, Zhejiang 315211, China. Tel.: +86 574 87600074; E-mail: [email protected].
Abstract: We propose using a circular driving electrode on a conventional thin film bulk acoustic wave resonator with a square piezoelectric film on a square ground electrode and a square dielectric layer. The circular driving electrode has the advantage of avoiding the electric field concentration at the corners of a square driving electrode and the related negative effects. A circular driving electrode is also perfectly consistent with the in-plane material isotropy of common thin film resonator materials such as AlN and ZnO. A theoretical analysis on the proposed resonator was performed to obtain the basic vibration characteristics including resonant frequencies and mode shapes.
