P. Parisse

Photoluminescence submicrometre spatial modulation of 6,13 pentacenequinone thin films

We demonstrate that uniform films of 6,13-pentacenequinone (PQ) deposited by vacuum thermal evaporation on prepatterned PMMA/Si(1 0 0) substrates yield under UV illumination a yellow photoluminescence (PL) response with strong spatial modulation at the micrometre (and submicrometre) scale. The PL patterns are obtained from engineered lithographed substrates (arrays of PMMA lines on bare Si(1 0 0) fabricated by x-ray interference lithography, using a tabletop 46.9 nm Ar laser). Strongly enhanced light emission is observed in correspondence to the PQ film lying on the PMMA lines with a PL efficiency 10 ± 1 times higher than the one measured on the PQ/Si interface.

Submicron patterning of a catalyst film by scanning probe nanolithography for a selective chemical vapor deposition of carbon nanotubes

Submicrometric catalyst patterns have been fabricated by atomic force nanolithography and the subsequent selective growth of carbon nanotubes has been successfully verified. Rectangular stripes (∼350 nm wide) were engraved onto a polymethylmethacrylate film, deposited onto SiO2/Si, by polymer removal with atomic force microscopy nanoindentation. Metallic catalyst patterns were subsequently obtained after 3 nm Ni deposition and lift-off of the residual polymer. Multiwalled carbon nanotubes were then grown by thermal chemical vapor deposition onto the Ni stripes. The various steps of nanopatterning and of carbon nanotubes growth are also studied by scanning electron microscopy and Raman measurements.