Controlled deposition of carbon nanotubes on a patterned substrate

We describe a new technique for the preparation of reactive templates of 1,2-aminopropyltriethoxysilane on silica surfaces, based on the chemical vapour deposition of silane molecules through a PMMA mask patterned by conventional electron-beam lithography. The template thickness and width are controlled down to the monolayer and 50 nm ranges respectively. These templates are successfully used for the selective deposition of sodium dodecylsulphate-covered single walled nanotubes at controlled locations on the surface. We demonstrate that this technique allows one to contact nanotubes with metallic electrodes deposited on top of the tubes and opens the way towards the formation of controlled crossings of nanotubes. (C) 2000 Elsevier Science B.V. All rights reserved.