Thermochemical nanopatterning of organic semiconductors
Publication date: Sep 22, 2009 9:57:27 AM
Oliver Fenwick,
Laurent Bozec,
Dan Credgington,
Azzedine Hammiche,
Giovanni Mattia Lazzerini,
Yaron R. Silberberg
&
Franco Cacialli
Nature Nanotehnology doi:10.1038/nnano.2009.254
Patterning
of semiconducting polymers on surfaces is important for various
applications in nanoelectronics and nanophotonics. However, many of the
approaches to nanolithography that are used to pattern inorganic
materials are too harsh for organic semiconductors, so research has focused on optical patterning and various soft lithographies. Surprisingly little attention has been paid to thermal, thermomechanical and thermochemical patterning.
Here, we demonstrate thermochemical nanopatterning of poly(p-phenylene vinylene), a widely used electroluminescent polymer, by a scanning probe. We produce patterned structures with dimensions below 28 nm, although the tip of the probe has a diameter of 5 µm, and achieve write speeds of 100 µm s-1. Experiments show that a resolution of 28 nm is possible when the tip–sample contact region has dimensions of 100 nm and, on the basis of finite-element modelling, we predict that the resolution could be improved by using a thinner resist layer and an optimized probe. Thermochemical lithography offers a versatile, reliable and general nanopatterning technique because a large number of optical materials, including many commercial crosslinker additives and photoresists, rely on chemical mechanisms that can also be thermally activated.
