Reducing anchor loss in piezoelectric-on-silicon laterally vibrating resonators by combination of etched-slots and convex edges

In this paper, we report enhancements by over 9 times in the quality factor (Q) of thin film piezoelectric-on-substrate (TPoS) MEMS resonators through engineering their acoustic modes. Specifically, we considered the effectiveness of using slots and convex curving of the resonator edges on reducing anchor loss to improve Q. The higher factor of improvement reported here compared to previously reported lamb-wave resonators based only Aluminum Nitride (AlN) and metal is likely due to lower interfacial losses when silicon is added to the structure, which also reduces thickness vibrations that are typical of lamb modes of vibration.