Thermoelastic damping in micro-wedged cantilever resonator with rectangular cross-section

Abstract

With the development of advanced manufacturing technologies of Micro-electro-mechanical Systems (MEMS), microbeams with variable cross-section have broad application in a wide range of resonators, such as stepped beam and tapered beam. As a fundamental and important energy dissipation mechanism in micro-resonators, thermoelastic damping (TED) is generally predicted by the classical Zener's model and LR's (Lifshits and Roukes) model. However, the two models are only suitable for uniform beams but except for non-uniform beams. In this paper, an appropriate TED model in micro-wedged cantilever resonator with rectangular cross-section is presented based on Zener's theory. Comparison with Finite Element Method (FEM) results, a perfect agreement proves that our model is correct and effective to evaluate TED in micro-wedged cantilever resonator. The results indicate that the quality factor of micro-wedged cantilever resonator is higher than that of uniform microbeam resonator in most cases and the Debye peak value of micro-wedged cantilever is about 0.43ΔE, which is smaller than 0.5ΔE of uniform microbeam.