MEMS based resonators

Abstract

One of the first resonators to reach Signal to noise ratios of 150 dB for Global System Mobile communication purposes was a square extensional plate MEMS resonator [1]. Typical resonators like such, have been incorporated into applications such as signal filtering, time referencing as well mechanical and motion sensing. This is possible due to the very high reference frequencies they are able to produce, in no small part because of their small size. The key concept regarding such devices lies in the topological as well as the material based structure, where through these properties, structures can be impelled to undergo different resonance modes, thus opening a wide range of possibilities for integrating these structures with other circuit components. For ideal resonators that exhibit high selectivity for particular frequencies and thus have a more pronounced and narrow bandwidth around this selective region, it is still necessary to incorporate electronic propriety and determine qualitatively how such a resonator can be most effectively applied. Thus by determining the parameters required for a MEMS resonator architecture to produce particular effects, the previously mentioned aim can be achieved. Which is why, for this dissertation, a MEMS resonator was tested through CoventorWare using finite element analysis, and replicated using MEMS+. The simulation results for either software were then compared with each other, after which the model created in MEMS+ was then exported to Cadence Virtuoso. Further analysis was then carried out to determine what factors could contribute to a more desired behaviour from the device, in terms of its Q-factor and the implied frequency selective region, as well as what applications could arise from it as a result.