Spatial Confined Chemical Reactions

Current and future developments in the microelectronics and biotechnology industries require successful nanofabrication technologies capable of extremely high spatial precision. Nanostructures need to be constructed in both two and three dimensions. we introduce a method capable of building 3D nanostructures. First, nanostructures of functionalized thiol SAMs are produced using an AFM-based nanolithographic method, nanografting. Then, a new reactant is introduced to attach to the reactive termini on the nanoengineered areas, resulting in the selective attachment to the 2D nanostructures, i.e., 3D nanofabrication. The spatial precision of this 3D nanofabrication process is determined by the quality of the 2D nanopatterns and by the selectivity of the pattern transfer reaction.

Pattern transfer through a nanoconfined chemical reaction
Current and future developments in the microelectronics and biotechnology industries require successful nanofabrication technologies capable of extremely high spatial precision. Nanostructures need to be constructed in both two and three dimensions. we introduce a method capable of building 3D nanostructures. First, nanostructures of functionalized thiol SAMs are produced using an AFM-based nanolithographic method, nanografting. Then, a new reactant is introduced to attach to the reactive termini on the nanoengineered areas, resulting in the selective attachment to the 2D nanostructures, i.e., 3D nanofabrication. The spatial precision of this 3D nanofabrication process is determined by the quality of the 2D nanopatterns and by the selectivity of the pattern transfer reaction.

	(A) Two MUD nanopatterns (50 × 50 nm2 and 100 × 100 nm2) are produced using nanografting. Fabrication and imaging are carried out in a decahydronaphthalene solution containing 0.4 mM MUD. (B) The same nanopatterns 10 min after reaction with 10 mM OTS in decahydronaphthalene. The height of the nanostructures increased by 2.3 ± 0.4 nm. (C) A square nanoframe (300 × 300 nm2) of ODT/Au(111) was grafted into the MUD/Au(111) matrix. The width of the frame is 100 nm. (D) The same area after reaction with 10 mM OTS in decahydronaphthalene for 3 min. The height of the matrix areas increased by 1.7 ± 0.5 nm. As a result, the nanoframe exhibits negative contrast in the topographic image.
Publications: (1). Liu, J.-F.; Cruchon-Dupeyrat, S.; Garno, J. C.; Frommer, J.; Liu, G.-Y.; Nano Lett.; 2002; 2(9); 937-940