| AVS 54th International Symposium | |
| MEMS and NEMS | Monday Sessions |
| Session MN-MoM |
| Session: | Materials Processing, Characterization and Fabrication Aspects |
| Presenter: | S.S. Verbridge, Cornell University |
| Authors: | S.S. Verbridge, Cornell University D. Finkelstein Shapiro, Cornell University H.G. Craighead, Cornell University J.M. Parpia, Cornell University |
| Correspondent: | Click to Email |
We have used optical drive and detection to study the mechanics of flexural nanostring resonators. Beam stress in devices made of both silicon and silicon nitride is tuned by macroscopically bending the resonator chip, resulting in a drastic tuning of the frequency of the correctly oriented doubly clamped beams. Frequency tuning by as much as several hundred percent is achieved with this technique. Over this wide range of frequency tuning, quality factor is also observed to be tuned by as much as several hundred percent. Highly stressed devices display the highest quality factors, and we therefore conclude that stress can be used as a parameter to increase device performance by increasing both resonant frequency as well as quality factor. Frequency can be drastically tuned and quality factor positively impacted by the addition of both tensile, as well as compressive stress. We discuss the sources of dissipation for these devices, and demonstrate a high tensile stress doubly-clamped beam resonator with sub-micron cross-sections, and a quality factor of 390,000 at 3.7 MHz, in vacuum, and at room temperature. The high frequency and quality factor exhibited by the high stress devices, as well as the significant tuning attained with the chip-bending technique, should prove useful for applications of nanomechanical resonant devices.