Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Theory of thermoelastic damping in electrostatically actuated microstructures Sudipto K. De and N. R. Aluru

Summary: Theory of thermoelastic damping in electrostatically actuated microstructures
Sudipto K. De and N. R. Aluru
Department of Mechanical Science and Engineering, Beckman Institute for Advanced Science and Technology,
University of Illinois at Urbana-Champaign, 405 N. Mathews Avenue, Urbana, Illinois 61801, USA
Received 6 July 2006; published 17 October 2006
Thermoelastic damping TED is an inherent energy dissipation mechanism in micromechanical resonators
which imposes an upper limit on the quality factor. Micromechanical resonators with very high quality factors
are essential for many applications. Electrostatic actuation is a very common mode of actuation for microreso-
nators and microstructures referred to as electrostatic microelectromechanical systems . The nonlinear elec-
trostatic actuation force can significantly alter the nature of thermoelastic damping, and hence the quality factor
QTED of the microstructures, from that predicted by the classical theory of thermoelastic damping developed by
Zener Phys. Rev. 52, 230 1937 ; 53, 90 1938 and later improved by Lifshitz and Roukes Phys. Rev. B
61, 5600 2000 . In this paper, the classical theory of thermoelastic damping is modified for application to
microstructures under arbitrary electrostatic actuation. The higher-order harmonics of the excitation frequency,
which can be present in the oscillations due to the nonlinear nature of the electrostatic force, are taken into
account in the modified theory. A physical level simulation tool is also developed in this paper based on
coupled electrostatic, fluidic, and large-deformation thermoelastic analysis and validated by comparing with
experimental data. The simulation results from the physical level analysis are compared with the predictions of
the classical theory and the modified theory under electrostatic actuation. While significant differences both
quantitative and qualitative are observed in the thermoelastic quality factor QTED obtained from the physical


Source: Aluru, Narayana R. - Department of Mechanical and Industrial Engineering, University of Illinois at Urbana-Champaign


Collections: Engineering; Materials Science