Analysis of Mechanical Fatigue Behavior for MEMS Structures

Abstract:

Fatigue of MEMS structures may occur after cyclic vibration loading, which can lead to the material degradation. A test bench was built for mechanical fatigue testing, especially for the structures that actuated by electrostatic force. A RF MEMS switch which was made of gold was tested; the material mechanical characteristic was monitored during the tests by means of the value of pull-in voltage, which is related to the change of the Youngs modulus. The fatigue stress was produced by an alternating voltage, and the amplitude of which is from 15V to 65V. The excitation frequency and the actuation time were used as a counter for the number of cycles. The results show that there is no detectable mechanical fatigue after actuation up to one billion cycles.

• Periodical: Applied Mechanics and Materials (Volumes 511-512)
• Pages: 565-568
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.511-512.565
• Online since: February 2014
• Authors: Qin Wen Huang*, Xiang Guang Li, Yun Hui Wang
• Keywords: Fatigue, Pull-In Voltage, Rf MEMS Switch

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