| AVS 62nd International Symposium & Exhibition | |
| MEMS and NEMS | Tuesday Sessions |
| Session MN+MG-TuM |
| Session: | Multiscale Phenomena & Interactions in Micro- and Nano-Systems (8:00-10:00 am) & Optical MEMS/NEMS, Photonics, and Quantum Nanosystems (11:00 am-12:20 pm) |
| Presenter: | Jocelyn Westwood-Bachman, University of Alberta and The National Institute for Nanotechnology, Canada |
| Authors: | J.N. Westwood-Bachman, University of Alberta and The National Institute for Nanotechnology, Canada W.K. Hiebert, University of Alberta and The National Institute for Nanotechnology, Canada |
| Correspondent: | Click to Email |
Nanomechanical systems are well known for their mass sensitivity, and are often used as mass sensors [1]. However, nanomechanical sensors tend to operate poorly in liquid environments due to viscous damping by the surrounding fluid. This drawback is particularly challenging for biological and related clinical sensing applications, where it is ideal to detect molecules within a liquid environment [2]. Here, we show the design of a fin-like nanomechanical resonator specifically for use in liquid environments. This design features a cantilever pointing out of the plane of the silicon device layer. This is in contrast to typical cantilevers that are in the silicon plane. The length of the cantilever is determined by the thickness of the silicon layer used, and the thickness of the resonator is designed to achieve specific resonance frequencies. The motion of these fin-like resonators is read out by an adjacent photonic microring resonator [3]. This microring resonator also provides an avenue for optical actuation of the fin resonator. The benefit of this design over existing designs is twofold. Firstly, our integrated photonics detection and actuation scheme provides higher displacement sensitivity than interferometric techniques [4]. Secondly, the fin is designed to operate at high frequencies (above 500 MHz) but can still have comparable surface area to nanoscale cantilevers as the width can be made arbitrarily large. This increases the sensing area while reducing the overall dissipation [5]. We will illustrate our design methodology and show the first generation of devices. As the as-fabricated devices have larger-than-desired feature sizes due to the limitations of photolithography, we will also discuss potential methods of tuning the device size post-fabrication. Specifically, we explore the possibility of trimming the fin resonator using Ga and He ion milling.
[1] M S. Hanay et al, Nature Nanotech. 7, 602 (2012)
[2] J. Tamayo et al, Chem. Soc. Rev. 42, 1287 (2013)
[3] V. T. K. Sauer et al, Nanotechnology, 25, 055202 (2014)
[4] Z. Diao et al, Appl. Phys. Expr. 6, 065202 (2013)
[5] K. L. Ekinci et al, Lab Chip 10, 3013 (2010)