Investigation of the Nanoparticle Electrical Contact Lubrication in MEMS Switches

A nanoparticle has been reported as a promising lubricant to increase the durability of microelectromechanical systems (MEMS) switches, but there remains much room for development and scientific observations. In this paper, we present the fabrication and research platform for a nanoparticle lubricated MEMS switch; we measured its characteristics and investigated the mechanisms behind it. In the measurements, gold nanoparticle lubrication demonstrated an increased average adhesion force from 16.38 to 23.68 $\mu \text{N}$ by 44.51% and a decreased average electrical contact resistance from 211.20 to 49.85 $\text{m}\Omega $ by 76.40%. In a hot switching mode lifetime test, the gold nanoparticle lubricated MEMS switch exhibited extension of reliability from $5.13\times 10^{4}$ to $4.75\times 10^{5}$ cycles, which corresponds to 9.26-fold increase. We attribute this remarkable enhancement to a mechanical stress release via lateral deformation of the nanoparticle and refreshment of the contact spots owing to movement of nanoparticles. [2017-0127]