The Role of Surface Topography in MEMS Switches and Relays

Microelectromechanical systems (MEMS) technology employed to generate switches and relays has the potential to replace traditional solid-state devices due to broader operating temperature range, higher breakdown voltage, and much higher off-state resistance. Interest in MEMS switches and relays has surged recently, principally due to the demonstrated performance in switching radio-frequency signals. The role of surface topography in the performance and lifetime of MEMS switches and relays is the objective of this review paper. Special emphasis is given to an approach that accounts for effect of roughness and to the role of surface topography in the pull-in voltage and contact bouncing. A critical assessment of emerging topics where experimental and theoretical studies are still required in order to obtain better insight into the role of surface topography in MEMS switches and relays is presented.