| AVS 65th International Symposium & Exhibition | |
| MEMS and NEMS Group | Thursday Sessions |
| Session MN+2D+AN+NS-ThA |
| Session: | Nonlinear and Thermal Resonators |
| Presenter: | Martial Defoort, CEA/LETI-University Grenoble Alpes, France |
| Authors: | M. Defoort, CEA/LETI-University Grenoble Alpes, France M. Sansa, CEA/LETI-University Grenoble Alpes, France M. Gély, CEA/LETI-University Grenoble Alpes, France G. Jourdan, CEA/LETI-University Grenoble Alpes, France S. Hentz, CEA/LETI-University Grenoble Alpes, France |
| Correspondent: | Click to Email |
Micro/Nano-ElectroMechanical Systems (M/NEMS) have attracted much attention in the last years in the mass spectrometry field. They feature high sensitivity, charge independent and single particle detection capabilities, in a mass range where conventional mass spectrometry struggles, hampering the analysis of large mass objects like protein complexes or viruses [1-4].
In general the size and mass of the device defines the size and mass ranges of the particles to measure for frequency tracking and point mass approximation purposes. However, as many silicon M/NEMS are electrostatically actuated, the gap between the driving electrode and the resonator becomes a critical parameter. While for many applications this gap should be as small as possible for high efficiency actuation and high signal-to-noise ratio, a particle landing within the gap results in a catastrophic failure of the device through electrical short-circuit or mechanical anchoring.
We present a new actuation scheme for doubly-clamped beams which rel ies on the thermal expansion of nano-actuators in silicon due to Joule heating, located close to the anchor of the resonator (Fig. 1), that we demonstrate to work in an array of 20 NEMS (Fig. 2). Unlike some thermoelastic actuation schemes [5], the technique we propose does not require an additional layer (of, for example, a metal) and is readily CMOS-compatible. Because of their small size and thermal capacity, the thermal time constant of the actuators is small enough to drive the resonator up to several 100’s MHz with large efficiency and to actuate the two first flexural modes of the same device simultaneously, which is required for single particle mass sensing . The detection scheme uses the piezoresistive gauges located on the other end of the beam, as previously presented [6]. We compare the performance of this actuation technique with a standard electrostatic scheme both on the same array and demonstrate the thermal actuation does not affect the level of frequency fluctuations limiting the device mass resolution (Fig. 3).
1. Hanay et al, nature nanotechnology 2012.
2. Sage et al, nature communications 2015.
3. Sage et al, Arxiv 2017.
4. Dominguez-Medina et al, Arxiv 2018.
5. Mo Li et al, nature nanotechnology 2007.
6. Mile et al, nanotechnology 2010.