Thickness-shear Modes and Energy Trapping in a Rectangular Piezoelectric Quartz Resonator with Partial Electrodes

摘要

We analyze thickness-shear vibrations of a rectangular plate of quartz piezoelectric crystal for acoustic wave resonator application. The plate is partially electroded in the central region. The scalar differential equation derived by Tiersten and Smythe is employed. Exact solution for the free vibration resonant frequencies and modes are obtained. Trapped modes with vibrations mainly under the electrodes are found. The results are useful to the understanding and design optimization of crystal resonators.