Two dimensional, high electromechanical coupling aluminium nitride Lamb wave resonators

Novel checker-patterned AlN piezoelectric Lamb wave resonators with applications in radio-frequency microelectromechanical systems (RF MEMS) are reported in this paper. In this work, diamond shaped electrodes are arranged on a plate of AlN in a checkered formation. When out-of-phase alternating currents are applied to adjacent checkers, acoustic Lamb waves are excited in the piezoelectric layer in two directions, achieving electromechanical coupling coefficients comparable FBARs. The simulated resonator presented in this paper resonates at 2.34GHz and achieves electromechanical coupling coefficients of 5.8%. By varying the electrode dimensions and inter-electrode distancing, several resonators of differing frequencies can be fabricated on a single wafer, allowing this device to provide novel solutions in broadband filters, duplexers and multiplexers. To verify this concept, a filter with bandwidth of 102 MHz at the center frequency of 2.4 GHz based on Checker-mode resonators are simulated in this work.