Nanotribology of anti-friction coatings in MEMS

The polysilicon surfaces used to manufacture microelectromechanical systems are often coated with organic self-assembled monolayers (SAMs) to reduce the adhesion and friction. While a large body of work exists on this topic, there is still not a fundamental understanding of the friction and adhesion between SAM-coated surfaces. This article reviews recent work on the nanotribology of SAM-coated silica surfaces. In particular, extensive molecular dynamics simulations have been performed to understand the effects of surface coverage, chain length, and fluorination on friction and adhesion. Also studied were the effects of interstitial water between the silica substrate and the SAM.