Piezoelectric micro-scale tuning fork resonators for sensing applications

MEMS resonators have stimulated an increasing interest within the last years, and many applications of this technology in fields such as telecommunications, inertial sensors, as well as biosensors, have been demonstrated. The achievement of a high quality factor (Q factor) for these devices is a key issue to maximize their performance. Therefore, there is a continuous search for the structure and the corresponding mode of vibration that enhances the Q factor. Among the wide range of possibilities, the combination of tuning fork-shaped structures and the first anti-phase in-plane mode of such structures has already demonstrated its potential in the macroscopic scale for the fabrication of oscillators. So, here, we pay attention to piezoelectric-actuated tuning forks, but in the micro-scale. The obtained results are very promising, achieving a Q factor in air as high as 4344 for the first anti-phase in-plane mode.