Abstract
A geometry-specific excitation configuration has been used to suppress all undesired spurious modes around the center frequencies of stand-alone micromechanical extensional wine-glass ring ("ext. WGR") resonators, previously demonstrated at frequencies up to 1.47-GHz with Q's >2,000 [1]. Using this technique, spurious modes at 406.7, 418, and 419 MHz, normally observed near the resonance of a 415-MHz ext. WGR, have been removed, as have all spurious modes within at least a 50% bandwidth region around the resonance. In removing unwanted modes, this technique solves one of the most encumbering issues with ring-type (as opposed to disk-type [2] ) GHz resonators, and paves the way for their use in the micromechanical oscillator and filter circuits targeted for future wireless transceivers [3]. © 2005 IEEE.