Applied Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 253, D-69120 Heidelberg, Germany
The development of simple and rapid techniques for the site-specific immobilization of single molecules or molecular aggregates is a central objective in nanoscience. A promising strategy to reach this goal is the combination of well established "top-down" lithographic techniques with novel "self-assembling" materials. In my presentation, I shall show that electron beams are ideal tools to modify self-assembled monolayers (SAM) of amphiphilic molecules and that e-beam lithography allows the fabrication of SAM nanostructures with lateral dimensions down to ~10 nm. Such patterned SAMs can be used as ultrathin resists  and as high resolution templates for a laterally controlled electrochemical deposition . SAMs of nitropbiphenylthiol (NBT) are particularly useful for e-beam patterning, as electrons convert the terminal nitro groups into amino groups while the underlying aromatic substrate is dehydrogenated and cross-linked . Hence, e-beam lithography creates a template of localized surface amino groups to which other molecules may be coupled so that molecularly distinguished nanostructures are generated . The procedure can be multiply repeated and molecular patterns with different chemical characteristics may be generated within one surface. Templates generated by this "chemical" nanolithography can be used to immobilize various molecular entities, such as dyes, polymers, oligonucleotides and proteins on different surfaces.