Thermoelastic Damping in Cone Microcantilever Resonator

[摘要] Microbeams with continuous or discontinuous variable cross-section have been applied in Microelectromechanical Systems (MEMS) resonators, such as tapered microbeam, torsion microbeam and stepped microbeam. Thermoelastic damping (TED), which is verified as a fundamental energy lost mechanism for microresonators, is calculated by the Zener's model and Lifshits and Roukes's (LR) model in general. However, for non-uniform microbeam resonators, these two classical models are not suitable in some cases. On the basis of Zener's theory, a TED model for cone microcantilever with rectangular cross-section has been derived in this study. The comparison of results obtained by the present model and Finite Element Method (FEM) model proves that the proposed model is able to predict TED value for cone microcantilever. In addition, TED in cone microcantilever is nearly same as TED in wedge microcantilever. The results show that quality factors (Q-factors) of cone microcantilever and wedge microcantilever are larger than Q-factor of uniform microbeam at low frequencies. The Debye peak value of a uniform microcantilever is equal to 0.5ΔE, while those of cone microcantilever and wedge microcantilever are about 0.438ΔEand 0.428ΔE, respectively.

[发布机构] School of Mechanical Engineering, Southeast University, Jiangsu, China^1

[效力级别] 无线电电子学

[关键词] Finite element method model (FEM);Micro resonators;Micro-cantilevers;Microelectromechanical systems resonators;Quality factors;Rectangular cross-sections;Thermoelastic damping;Variable cross section