Vibration Mode Suppression in Micromechanical Resonators Using Embedded Anti- Resonating Structures

This paper presents a technique for suppressing specific resonance modes of micromechanical resonators by mechanical means. In particular, attaching multiple miniaturized beam structures with properly designed dimensions acting as anti-resonating tuned mass dampers (TMD's) to a micromechanical clamped-clamped beam (CC-beam) resonator based on a CMOS-MEMS process platform successfully attenuate the dynamic frequency response of the fundamental mode while retaining the 2
^nd
harmonic mode of the CC-beam. The measured results show that the frequency transmission response of the TMD-embedded CC beam drops as much as ~12 dB compared to that of a reference resonator. An analytical model is used to study the effects of the parameter variations of the TMD structures. This technique provides an alternative approach to mechanically suppressing vibration modes for the micromechanical resonators that cannot employ the conventional quarter-wavelength support technique.