Design and Optimization for Double-Sided Interdigital Transducer with Piezoelectric Substrate

The interdigital transducer (IDT) is the most basic unit of the surface acoustic wave device. The optimization design of double sides IDT can make contribution to the improvement of driving performance. In this paper, the finite element analysis method was used to calculate the influence between the geometry parameters and the driving performance of double-sided IDT based on a piezoelectric substrate utilizing COMSOL Multiphysics. And the effect of electrode width and electrode gap on the driving strain under IDT unit voltage was also analyzed. The results show that the smaller the thickness of the substrate, the more helpful of improving the driving sensitivity of the IDT. The driving voltage was reducing with the decreasing of the electrode gap. And the optimal piezoelectric driving performance can be obtained when w / t =0.33. This work provides theoretical guidance for the optimal design of double-sided IDT.