Asymmetrical mechanical design for bouncing suppression in RF-MEMS switches

Contact bouncing is among the most critical phenomenon reducing RF-MEMS reliability. This paper shows that very simple changes in switch design permit suppression of contact bouncing upon closure. The proposed asymmetrical design gets two dimples in contact with substrate electrodes successively, instead of simultaneously. This helps the dissipation of kinetic energy and prevents contact re-opening. On top of preliminary ageing prevention, the structure can handle more actuation voltage and then have more contact force compared to symmetrical structures. Experimental demonstration is presented on metal contact switches with more than 2mN contact force, one symmetrical with significant bouncing and the other asymmetrical without any bouncing clearly show the relevance of the approach.