Fabrication of nanometer scale patterns within self-assembled monolayers by nanografting

A nanofabrication method, nanografting, has been developed to fabricate nanometer scale patterns on surfaces with specified size and geometry. The nanografting process combines the displacement of selected resist molecules by an atomic force microscopy tip and the adsorption of new adsorbate. The present work details the procedure for nanografting and discusses various kinds of patterns produced and the stability of the resulting patterns. Compared with other methods for microfabrication, nanografting allows a more precise control over the size and geometry of patterned features and their locations on surfaces. Nanopatterns comprising various thiol-based components can be produced, where we have demonstrated the fabrication of nanopatterns from thiols with either the same or different chain lengths and terminal groups from the matrix SAM. Furthermore, nanografting allows the fabricated patterns to be altered in situ without the need to change masks or repeat entire fabrication processes. The patterned SAMs produced by nanografting open new opportunities for systematic studies of such size-dependent properties as conductivity, nanotribology, and spatially-confined surface reactions.