Thin film bulk acoustic wave piezoelectric resonators with circular ring driving electrodes for mass sensing

Abstract

We study thickness-extensional vibration frequencies and modes in a thin ZnO or AlN film on a silicon layer with a circular ring driving electrode. It is shown that the vibration tends to be trapped in the annularly electroded area and decays away from the electrode edges. The convexity of the vibration distribution near the film center can be adjusted through design, and can be made nearly uniform for mass sensor application. The theoretical analysis presented can be used to optimize the design of the device.

Keywords:

• Piezoelectric
• plate
• vibration
• resonator
• sensor

Additional information

Funding

This research was supported by the National Natural Science Foundation of China (Nos. 11672141 and 11372145), the Y. K. Pao Visiting Professorship at Ningbo University, and the K. C. Wong Magana Fund through Ningbo University.