Nanoscale patterning of organic molecules has received considerable attention in current nanoscience for a broad range of technological applications. In order to provide a viable approach, this thesis describes catalytic stamp lithography, a novel soft-lithographic process that can easily produce sub-100 nm patterns of organic monolayers on surfaces. Catalytic stamps were fabricated through a two-step procedure in which the nanoscale patterns of transition metal catalysts are first produced on SiOx/Si surfaces via the use of self-assembled block-copolymers, followed by the production of the poly(dimethylsiloxane) (PDMS) stamps on top of the as-patterned metals. Simply peeling off the as-formed PDMS stamps removes the metallic nanostructures, leading to the functional stamps. A number of different patterns with various metals were produced from a commercially available family of block copolymers, polystyrene-block-poly-2-vinylpyridine, by controlling the morphology of thin-film templates through the modulation of molecular weights of polymer blocks or solvent vapor annealing. Using these catalytic stamps, hydrosilylation-based catalytic stamp lithography was first demonstrated. When terminal alkenes, alkynes, or aldehydes were utilized as molecular inks, the metallic (Pt or Pd) nanopatterns on catalytic stamps were translated into corresponding molecular arrays on H-terminated Si(111) or Si(100) surfaces. Since localized catalytic hydrosilylations took place exclusively underneath the patterned metallic nanostructures, the pattern formations were not affected by ink diffusion and stamp deformation even at the sub-20 nm scale, while maintaining the advantages of the stamp-based patterning (i.e., large-area, high-throughput capabilities, and low-cost). The concept of catalytic stamp lithography was further extended with other catalytic reactions, and successful nanoscale patterning was performed using hydrogenation (on azide-terminated SiOx surfaces) and the Heck reaction (on alkene- or bromphenyl-terminated SiOx surfaces). A range of nanopatterned surfaces with different chemical functionalities, including thiol, amine, and acid, were created, and they were further modified through appropriate chemical reactions. The potential utility of this simple approach for the construction of a higher degree of nanoarchitectures was suggested.

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La fonctionnalisation de surfaces de silicium hydrogéné par des films de molécules organiques suscite un intérêt croissant en raison des nombreuses applications potentielles (photovoltaïsme, détection chimique et biochimique, électronique moléculaire...). Dans ce cadre, nous avons cherché à greffer des tétrathiafulvalènes ou des complexes dithiolène de platine à ligand bipyridine, électroactifs, sur cette surface par hydrosilylation d’alcynes. Nous avons montré que ces composés organiques étaient bien immobilisés par une liaison robuste Si-C et nous avons noté la présence de plusieurs états redox stables et réversibles associés aux molécules greffées. Les méthodes de greffage direct et de post-fonctionnalisation de monocouches, ont permis l’obtention de films denses stables aux constantes de transfert de charge élevées. / The functionalization of silicon surfaces by thin layers of organic molecules raises increasing interest due to the large extent of potential applications (photovoltaics, chemical and biochemical detection, molecular electronics and so on). In this context, we have prepared TTF and platinum dithiolene complex-modified silicon surfaces through a hydrosilylation reaction between hydrogen-terminated silicon and alkyne-terminated precursors. We have shown that these organic compounds were covalently bound to the surface through a robust Si-C bond. We have demonstrated that the electroactivity of the grafted molecules characterized by several reversible one-electron systems was maintained after the immobilization step. Post-functionalization and direct grafting reactions lead to dense and stable films, with high values of electron-transfer rate constants.