Reducing adhesion energy of nano-electro-mechanical relay contacts by self-assembled Perfluoro (2,3-Dimethylbutan-2-ol) coating

To enable energy-efficient electronic devices for the future, nano-electro-mechanical (NEM) relays are promising due to their high ON/OFF current ratio and potential for low operating voltage. To minimize hysteresis and, consequently, relay operating voltage, it is imperative to reduce the relay contact adhesion, which can be achieved by coating the contacts with anti-stiction self-assembled monolayers. Herein we report a 71% reduction in hysteresis voltage by utilizing a branched perfluorocarbon antistiction molecule: Perfluoro (2,3-Dimethylbutan-2-ol) (PDB) on top of the tungsten contact surfaces. Experimental results show the operation of a PDB-coated NEM relay with abrupt switching, undetectably low OFF-state current, hysteresis voltage as low as 20 mV, and a large ON/OFF current ratio (>107).