Nanolithographic patterning

As a tool for nanotechnology, the STM has been well publicized in its ability to push or manipulate atoms into specific locations to create nanopattems. However, this is a relatively slow process and would not be commercially viable. A more feasible approach has been undertaken using the AFM to create nanolithographic patterns by using the tip to remove material from a siuface and create the desired pattern. 

Smalley and coworkers sought to employ self-assembly to fabricate CNT-based electronic devices, where individual SWNTs were deposited on chemically functionalized nanolithographic patterns." This method should enable the creation of nanotube-based circuits and structures according to a predesigned pattern. Prior to this approach, it was common for nanotubes to be deposited on an electrode array by either random deposition (i.e., drop casting) or using probe microscopy (AFM or STM) to position CNTs on the electrode. Their approach is an example of using carboxylated CNTs in noncovalent interactions. 

B. Basnar and 1. Willner, Dip-pen-nanolithographic patterning of metallic, semiconductor, and metal oxide nanostructures on surfaces. Small, 5, 28-44 (2009). 

Hyakutake T, Park JY, Yonekuta Y, Qyaizu K, Nishide H, Advincula R (2010) Nanolithographic patterning via electrochemical oxidation of stable poly(nitroxide radical)s to poly(oxoammonium salt)s. J Mater Chem 20 9616-9618... 

Poly(p-phenylenevinylene) (PPV) could be obtained in the form of nanotubes, nanorods and nanofilms by the chemical vapor deposition (CVD) polymerization of a,a -dichloro-/7-xylene followed by thermal dehydrochlorination. The polymerizations were conducted on the inner surface of or inside the nanopores of alumina or polycarbonate membrane filters or on the surface of silicon wafers. The PPVs thus obtained could be thermally converted to the corresponding carbonized tubes, rods, and films. We also could obtain nanopatterns and nanowells of PPV and carbon on silicon wafers by utilizing nanolithographed poly(methyl methacrylate) patterns. The PPV films obtained on the silicon wafers are semicrystalline and produce highly conducting (a 0.7 x 10 Scm ) graphitic films even when treated only at 850 C. Field-emission properties of some of the graphitic nanotubes are also described in this report. 

S. T. Liu, R. Maoz, G. Schmid, and). Sagiv, Template guided self-assembly of [Auss] clusters on nanolithographically defined monolayer patterns. Nano Lett, 2,1055-1060 (2002). 

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