US Patent 7144683 - Photopatternable Functional Groups for Molecular Electronics

http://www.freepatentsonline.com/7144683.pdf

Although there are not yet products on the market based on molecular electronics, Hewlett Packard has laid claim to a dominant position based on their R&D and numerous patents on the use of rotaxane and other molecular structures to create crossbar memories and other high density electronic structures. The fabrication of these devices is typically not compatable with conventional optical lithography approaches which usually require resists that may adversely affect the functional molecules being used. This patent proposes a solution involving photopatternable functional groups to replace the conventional resists. Claim 1 reads:

1. A method for fabricating a multiple electrode device comprising at least one pair of electrodes that form at least one junction and at least one connector species connecting said pair of electrodes in said junction, said junction having a functional dimension in nanometers or micrometers, wherein said at least one connector species comprises said bistable molecule provided with at least one photosensitive functional group for patterning said connector species, said method comprising: (a) forming a first set of said electrodes on a substrate; (b) depositing a film of said bistable molecule(s) including said at least one photosensitive group; (c) exposing portions of said bistable molecular film to desired radiation to thereby cause at least one of photochemical decomposition or photochemical transformation of said at least one photosensitive functional group; and (d) removing unwanted portions of said bistable molecular film to provide a photopatterned film.