Resonant properties of thin film bulk acoustic resonator (FBARs) with considering the two dimensional size effects

The piezoelectric thin film bulk acoustic resonators (FBARs) is a new kind frequency devices, which has exhibited several prominent advantages. In this paper, the typical models of FBAR are established to analyze modal resonance frequency with ANSYS codes. The results for the modal resonance frequencies vs. width-to-thickness aspect ratio were obtained. The effective electro-mechanical coupling factors were computed from the resonance and anti-resonance frequencies. The results showed that the structures with small width-to-thickness aspect ratios can be excited to yield a higher electromechanical coupling factor and effectively eliminate the spurious resonances from lateral modes of vibration.