Molecular lubricants for silicon-based microelectromechanical systems (MEMS): a novel assembly strategy

Microelectromechanical systems (MEMS) are poised to bring the next technolo gy revolution. At present, many of these are fabricated from silicon using lithographic techniques developed in the microelectronics industry. Due to the large surface area to volume ratio on the micrometer scale, surface for ces, such as adhesion and friction, are often detrimental to the fabricatio n and operation of MEMS devices. Thus, one of the key issues in MEMS is sur face engineering to reduce adhesion and friction. Here, we present a genera l strategy for the efficient assembly of organic layers directly onto the s ilicon surface in both vacuum environment and solution phases via the robus t Si-N or Si-O linkage. This is achieved by the reaction between an amine o r alcohol functional group and a chlorinated Si surface. The resulting surf ace assemblies are thermally stable. Characterization by interfacial force microscope (IFM) reveals that these assemblies have very low surface energy and are mechanically stable.