Influence of Electrode Duty Factor on the Performance of Lamb-Wave AlN Resonators on SOI Substrate

In this paper, we study the influence of electrode duty factor on the performance of AlN lamb-wave S0 mode resonators on SOI substrate. The lamb wave resonators reported are fabricated on a SOI substrate with the duty factors varying from 0.2 to 0.8. The electromechanical coupling coefficient and quality factor of resonators with each duty factor are calculated from the measurement results of admittance versus frequency by numerically fitting by the Butterworth Van Dyke model. The results show that when the duty factor is 0.67, the highest figure of merit is obtained with a high quality factor of 6722. This work may provide guidance for future AlN lamb-wave resonator design on SOI substrate.