Thermally Actuated Radio Frequency Nanomechanical Resonators and Oscillators

Funded by NSF

1.aIn this project, we use a single mask fabrication process to fabricate high frequency single crystal silicon resonators on SOI substrates. We have already shown that thermal actuation is suitable for high frequency electromechanical devices and as opposed to the general presumption, thermal actuation is a more suitable mechanism for higher frequency resonators with smaller dimensions. Thermally actuated resonators with frequencies up to 61 MHz have been successfully demonstrated. We have also studied temperature drift behavior of these thermally actuated high frequency resonators and demonstrated temperature compensation very close to zero TCF.

In the meantime further optimization of these devices is currently ongoing in the µnX lab. We are working towards obtaining frequencies in the GHz range, while at the same time reducing the power consumption in the order of a few µW for these resonators.

 

SELECTED PUBLICATIONS

  1. A. Rahafrooz, and S. Pourkamali, “Thermal-piezoresistive energy pumps in micromechanical resonant structures,” IEEE Transactions on Electron Devices, vol. 59, no. 12, pp. 3587–3593, December 2012.
  2. A. Hajjam, A. Logan, and S. Pourkamali, “Doping Induced Temperature compensation of thermally actuated micromechanical resonators via doping and bias current optimization,” IEEE Journal of Micro-Electro-Mechanical-Systems, vol. 21, no. 3, pp. 681–687, June 2012.
  3. A. Rahafrooz, and S. Pourkamali, “High frequency thermally actuated electromechanical resonators with piezoresistive readout,” IEEE Transactions on Electron Devices, vol. 58, no. 4, pp. 1205–1214, April 2011.
  4. A. Hajjam, A. Rahafrooz, and S. Pourkamali, “Sub-100ppb/ºC Temperature Stability in Thermally Actuated High Frequency Silicon Resonators via Degenerate Phosphorous Doping and Bias Current Optimization,” proceedings, IEEE International Electron Device Meeting (IEDM), 2010.
  5. A. Rahafrooz, and S. Pourkamali, “Fully Micromechanical Piezo-Thermal Oscillators,” IEEE International Electron Device Meeting (IEDM), 2010.
  6. A. Rahafrooz, and S. Pourkamali, “Thermo-electro-mechanical modeling of high frequency thermally actuated I2-BAR resonators,” Hilton Head 2010, solid-state sensor, actuator and Microsystems workshop.
  7. A. Rahafrooz, A. Hajjam, B. Tousifar, S. Pourkamali, “Thermal actuation, a suitable mechanism for high-frequency electromechanical resonators,” proceedings, IEEE MEMS conference, 2010, pp. 200-203.