MEMS Resonators and the Grand Challenges of Low Loss, Low Phase Noise Devices

Micro-electro-mechanical system (MEMS) based resonators offer a combination of ultra low energy loss and chip-scale integration compatibility, motivating enthusiastic efforts to mature this technology for applications in RF electronics systems. Particularly high impact applications include RF filters and oscillators. In both cases, game-changing system designs will be enabled by development of resonators with low loss (high quality factor, or Q). In addition, research has shown that both high Q and tailored nonlinearities can produce unprecedented phase noise performance.

This talk will discuss the two grand challenges associated with RF filters and oscillators--energy loss and oscillator phase noise dynamics. The first part of this talk will review the tremendous progress in the MEMS community towards high Q devices. The fundamental physical limits on energy loss and the path forward to reach these limits will be described. The second part of this talk will discuss phase noise in oscillators, with particular emphasis on the role of the mechanical resonator performance. Though the impact of Q on phase noise is well known through Lesson's model, a generalization of this theory will be introduced so that the role of mechanical nonlinearities can be better understood. The surprising result that nonlinear mechanical devices can be designed to improve phase noise will be discussed.