THE RESONANT BODY TRANSISTOR

With quality factors (Q) often exceeding 10,000, vibrating micromechanical res-onators have emerged as leading candidates for on-chip versions of high-Q resonators used in wireless communications systems, sensor networks, and clocking sources in microprocessors. However, extending the frequency of MEMS resonators generally entails scaling of resonator dimensions leading to increased motional impedance. In this dissertation, I introduce a new transduc-tion mechanism using dielectric materials to improve performance and increase frequency of silicon-based RF acoustic resonators. Traditionally, electrostatically transduced mechanical resonators have used air-gap capacitors for driving and sensing vibrations in the structure. To in-crease transduction efficiency, facilitate fabrication, and enable GHz frequencies of operation, it is desirable to replace air-gap transducers with dielectric films. In my doctoral work, I designed, fabricated, and demonstrated dielectrically transduced silicon bulk-mode resonators up to 6.2 GHz, marking the highest acoustic frequency measured in silicon to date. The concept of internal dielec