INVESTIGATION ON THE ELECTRICAL CONTACT BEHAVIORS OF RF MEMS SWITCHES USING NANO-INDENTER

Abstract

This paper presents a methodology of investigating electrical contact behaviors of radio frequency (RF) microelectromechanical system (MEMS) switches by using a nano-indenter. The setup simulates hot switching of radio frequency microelectromechanical system (MEMS) switches; cyclic contact test is conducted to characterize reliability of the contact material. The reliability of Au-to-Au contacts was characterized under different currents; electric contact between both ball tip and Si wafer coated with thin Au film was permanently broken after certain switching cycles. The surface of contact region was deformed by melting and it causes contact area decreasing and finally the electrical contact was broken. The procedure of the contact failure can be explained by the trace of penetration depth change of nano-indetner and SEM images of the micro-contact surface.