Mode selection for electrostatic beam resonators based on motional resistance and quality factor

An analytical comparison between the fundamental mode and higher modes of vibration for anelectrostaticbeam resonator is presented. Multiple mode numbers can be matched to a desiredresonance frequency through appropriate scaling. Therefore, it is important to determine which mode yields the best performance. A dynamic model of the resonator is derived and then used to determine the motionalresistance for each mode. The resulting equation provides the basis for comparing performance between modes using motionalresistance and quality factor. As a demonstration of the approach, a quality factor model that has been previously validated experimentally is introduced. Numerical results forsilicon resonators indicate that the fundamental mode can provide a lower motionalresistance and higher quality factor when the resonators under comparison have the same aspect ratio or the same stiffness.

Source: Journal of Applied Physics - December 6, 2016 Category: Physics Authors: Jeong Hoon Ryou and Jason J. Gorman Source Type: research