Nanoscale replication of MEMS/NEMS by surface functionalisation with self-assembled monolayers

G.M. Kim, B.J. Kim, M. Liebau, J. Huskens, D.N. Reinhoudt, and J. Brugger

University of Twente, MESA+ Research Institute, NanoLink Strategic Research
Orientation and Supramolecular Chemistry and Technology Group
P.O. Box 217, Enschede, The Netherlands

A method that enables to release micro/nanofabricated structures mechanically off the surface without using wet chemistry is presented. A self-assembled monolayer of dodecyltrichlorosilane forms a very uniform ~1.5-nm-thick anti-adhesion coating on the silicon dioxide surface. The structural layers (100-nm metal and SU-8 plastic) are formed directly onto the organic layer to make a variety of novel structures. First, nm-flat electrodes embedded in a polymer layer were made. Second, a microcontact printed monolayer was directly transfered into a metal structure by mechanical rupture of a thin film without wet transfer steps. Third, the monolayer's ability to cover the surface at nanometer scale was exploited to make novel scanning near-field optical probes. The combination of local 'bottom-up 'surface modification using SAMs and 'top-down' micro/nanoengineering methods opens a new toolbox for advanced nanostructuring of functional surface at low cost for application in bio-nanotechnology, MEMS and NEMS and scanning probes.