Micromechanical Resonators: AlN/3C-SiC Composite Plate Enabling High-Frequency and High-Q Micromechanical Resonators (Adv. Mater. 20/2012)

An AlN/3C–SiC composite is used to realize high‐frequency and high‐Q acoustic wave resonators by exploiting the third‐order quasi‐symmetric (QS3) Lamb wavemode, as described by C.‐M. Lin, Y.‐Y. Chen, and co‐workers on page 2722. The epitaxial 3C–SiC layer enhances the electromechanical coupling of the QS3 mode and boosts the Q due to the intrinsic low acoustic loss of SiC crystals. This AlN/3C–SiC composite plate structure enables production of high‐performance micromechanical acoustic wave resonators for frequency control and sensing applications.