Enhancement of Quality Factor Using Dummy Electrodes at Nonsymmetric In-plane Rotation Angles in LiTaO3/SiO2/Sapphire SAW Resonators

This work studied the effect of dummy electrodes applied on the LiTaO3/SiO2/Sapphire based SAW resonators at nonsymmetric in-plane rotation angles. With dummy electrodes, the suppression of energy leakage obliquely into the busbars due to the non-zero power flow angle (PFA) were confirmed by FEM simulations. The mechanism was analyzed by means of FEM simulations and the modes profiles, which exhibit an additional decay in the induced dummy regions after original decaying in the air gaps, resulting in the suppression of energy leakage into the busbars. The experimental results confirmed the validation of enhancement of quality factor Q by using dummy electrodes at nonsymmetric rotation angles.