Reducing adhesion energy of micro-relay electrodes by ion beam synthesized oxide nanolayers

Abstract

Reduction in the adhesion energy of contacting metal electrode surfaces in nano-electro-mechanical switches is crucial for operation with low hysteresis voltage. We demonstrate that by forming thin layers of metal-oxides on metals such as Ru and W, the adhesion energy can be reduced by up to a factor of ten. We employ a low-energy ion-beam synthesis technique and subsequent thermal annealing to form very thin layers (∼2 nm) of metal-oxides (such as RuO2 and WOx) on Ru and W metal surfaces and quantify the adhesion energy using an atomic force microscope with microspherical tips.