Contact resistance and lifecycle of an ohmic MEMS switch with single and multiple contact bumps

摘要

Microelectromechanical systems (MEMS) switches potentially have a wide range of applications due to their promising characteristics, but relatively low reliability limits implementation of these devices. Contact region degrades during operation that increases the resistance and lowers the lifecycle. In this paper we demonstrate how these parameters can be enhanced by changing the design of the switch. The devices of four types having different number of contact bumps and beams are fabricated by surface micromachining and tested in a cold switching DC regime. The switch with two bumps has about 25% lower contact resistance and almost two times longer lifecycle than the one-bump device. Using four beams instead of one gives threefold increase of the lifecycle, but does not reduce the resistance significantly.