The effective fabrication of chemically defined surface nanostructures is an important objective in fields such as molecular electronics, biochips or biosensors. A promising strategy towards this goal is the combination of well established "top-down" lithographic techniques with novel self-assembling materials.
Recently, we have found that electron irradiation converts the terminal nitro functionality of self-assembled monolayers (SAMs) of 4-nitrobiphenylthiol to an amino group, while the underlying aromatic layer is dehydrogenated and cross-linked [1,2]. Based on these results, we employed electron beam lithography to modify the terminal groups of specifically tailored aromatic SAMs so that molecules can directly bind to the exposed regions. This electron induced "chemical lithography" can create ultrahigh resolution (< 20 nm) templates for the site selective immobilization of molecules.
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