Analyzing thickness shear vibration of ZnO thin film with a viscoelastic layer

According to the linear piezoelectric theory, the frequency equation of thickness shear vibration is obtained for investigating the ZnO thin film with a layer of viscoelastic media. Fortunately, some useful results are harvested. From these results, we find that the relative resonant frequency significantly increases when the viscous coefficient is in the range of 0-2Ns/m². The relation between the relative resonant frequency and the density and thickness of the viscoelastic media also has been discussed. These need to be considered in the design of resonators.