On the analysis of spontaneous adhesion in MEMS

Spontaneous adhesion can seriously jeopardize the reliability of micro-electro-mechanical systems, both during the fabrication phase and in the operation conditions. For this reason, adhesion in MEMS has been the topic of abundant research works in the last decade. This paper aims at the formulation of a computational model in order to simulate the adhesion phenomena in various environmental conditions. The present approach is based on Finite Element (FE) simulations on a representative part of the surface. The micro-scale analyses include the contact behavior of the asperities and the mechanical deformation of the bulk material, which is comparatively modeled as elastic-plastic. The model validation has been based on a simple sphere-on-flat simulation. Some preliminary results are presented with reference to actual rough surfaces.