Thermal fatigue life estimation and delamination mechanics studies of multilayered MEMS structures

This paper is concerned with the application of a Physics of Failure (PoF) methodology to assessing the reliability of Micro-Electro-Mechanical-System (MEMS) switches. Numerical simulations, based on the finite element method (FEM) using a sub-domain approach, were performed to examine the damage onset (e.g. yielding) due to temperature variations and to simulated the crack propagation arising after thermal fatigue. In this work remeshing techniques were employed in order to develop a damage tolerance approach based on the assumption that initial flaws exist in the multi-layered structure due, for instance, to manufacturing processes and/or are originates after thermal fatigue, as preliminary experimental tests has shown.