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Damping Characteristics of a Microcantilever for Radio Frequency-microelectromechanical Switches

RF-MEMS 스위치용 마이크로 외팔보의 감쇠특성

  • Received : 2011.04.01
  • Accepted : 2011.05.24
  • Published : 2011.06.20

Abstract

A theoretical approach is carried out to predict the quality factors of flexible modes of a microcantilever on a squeeze-film. The frequency response function of an inertially-excited microcantilever beam is derived using an Euler-Bernoulli beam theory. The external force due to squeeze-film phenomenon is developed from the Reynolds equation. Slip boundary conditions are employed at the interfaces between the fluid and the structure to consider the gas rarefaction effect, and pressure boundary condition at both ends of fluid analysis region is enhanced to increase the exactness of predicted quality factors. To the end, an approximate equation is derived for the first bending mode of the microcantilever. Using the approximate equation, the quality factors of the second and third bending modes are calculated and compared with experimental results of previously reported work. The comparison shows the feasibility of the current approach.

Keywords

References

  1. Rebeiz, G. M., 2003, RF MEMS Theory, Design, and Technology, John Wiley & Sons, Inc., New Jersey.
  2. Czaplewski, D. A., Dyck, C. W., Sumali, H., Massad, J. E., Kuppers, J. D., Reines, I., Cowan, W. D. and Tigges, C. P., 2006, A Soft-landing Waveform for Actuation of a Single-pole Singlethrow Ohmic RF MEMS Switch, Journal of Microelectromechanical Systems, Vol. 15, No. 6, pp. 1586-1594. https://doi.org/10.1109/JMEMS.2006.883576
  3. Granaldi, A. and Decuzzi, P., 2006, The Dynamic Response of Resistive Microswitches : Switching Time and Bouncing, Journal of Micromechanics and Microengineering, Vol. 16, No. 7, pp. 1108-1115. https://doi.org/10.1088/0960-1317/16/7/002
  4. Hong, S. H. and Lee, S. I., 2010, Vibration Analys is of the Tapping AFM Microcantilevers Using Proper Orthogonal Decomposition, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 20, No. 4, pp. 414-421. https://doi.org/10.5050/KSNVE.2010.20.4.414
  5. Bao, M. and Yang, H., 2007, Squeeze Film Air Damping in MEMS, Sensors and Actuators A, Vol. 136, No. 1, pp. 3-27. https://doi.org/10.1016/j.sna.2007.01.008
  6. Sumali, H., 2007, Squeeze-film Damping in the Free Molecular Regime: Model Validation and Measurement on a MEMS, Journal of Micromechanics and Microengineering, Vol. 17, No. 11, pp. 2231-2240. https://doi.org/10.1088/0960-1317/17/11/009
  7. Meirovitch, L., 1967, Analytical Methods in Vibrations, Macmillan Publishing, Inc., NewYork.
  8. Veijola, T., Pursula, A. and Raback, P., 2005, Extending the Validity of Squeezed-film Damper Models with Elongations of Surface Dimensions, Journal of Micromechanics and Microengineering, Vol. 15, No. 9, pp. 1624-1636. https://doi.org/10.1088/0960-1317/15/9/003
  9. Lee, J. W., Tung, R., Raman, A., Sumali, H. and Sullivan, J. P., 2009, Squeeze-film Damping of Flexible Microcantilevers at Low Ambient Pressures: Theory and Experiment, Journal of Micromechanics and Microengineering, Vol. 19, No. 10, pp. 105029-1-14. https://doi.org/10.1088/0960-1317/19/10/105029
  10. Guo, X. and Alexeenko, A., 2009, Compact Model of Squeeze-film Damping Based on Rarefied Flow Simulations, Journal of Micromechanics and Microengineering. Vol. 19, No. 4, pp. 045026-1-7. https://doi.org/10.1088/0960-1317/19/4/045026
  11. Kinsler, L. E., Frey, A. R., Coppens, A. B. and Sanders, J. V., 1982, Fundamentals of Acoustics, John Wiley and Sons, New York.
  12. Pandey, A. K., Pratap, R. and Chau, F. S., 2007, Influence of Boundary Conditions on the Dynamic Characteristics of Squeeze Films in MEMS Devices, Journal of Microelectromechanical Systems, Vol. 16, No. 4, pp. 893-904. https://doi.org/10.1109/JMEMS.2007.901135
  13. Gallis, M. A. and Torczynski, J. R., 2004, An Improved Reynolds-equation Model for Gas Damping of Microbeam Motion, Journal of Microelectromechanical Systems, Vol. 13, No. 4, pp. 653-659. https://doi.org/10.1109/JMEMS.2004.832194
  14. Rao, S. S., 2004, Mechanical Vibrations, Prentice Hall, NewYork.
  15. http://en.wikipedia.org/wiki/Coefficient_of_determination.