A "molecular eraser" for dip-pen nanolithography

An erasing method for repairing defective nanostructures generated in a dip-pen nanolithography (DPN) using conductive tip and conductive atomic force microscope (c-AFM) to electrochemically induce desorption is described. c-AFM would be used to selectively desorb portions of a monolayer-based structure made by DPN with alkanethiol inks on gold. c-AFM is used to selectively control the elimination of 16-mercaptohexadecanoic acid (MHA) nanostructures. This erasing technique can be coupled with DPN, and the eliminated MHA features can be backfilled with a new ink by simply coating the cantilever with the desired molecule. This procedure results in the elimination of the MHA-based triangle and replacement with a 11-ferrocenyl-1-undecanethiol (FUT) based compound without a damage to the 1-octadecanethiol (ODT)-coated regions of the substrate.