Unanticipated results in the first direct measurements of anchor damping in MEMS resonators

In this study, a novel method of measuring the Quality Factor (Q) of a MEMS tuning fork resonator at low temperature enabled us to accurately pinpoint the energy dissipation resulting from anchor damping [1]. We used this new method to perform the first direct examination of the impact of design of the anchors and the die mounting structures on the strength of anchor damping. Our results show that the elastic energy can escape the resonator through the anchor(s), and still be retained within the die, and that energy stored in the die can return to the resonator. Thus, the measured Q of the resonator is increased, depending on mounting structures far from the resonating element. Moreover, our data shows that the number of anchors does not change the total energy dissipation through the anchors.