microscope image of a nano-textured surface; each conducting
polymer fibril is 50nm in diameter.
||Dr Ali Rashid inspecting a tube containing
purified pentacene crystals.
Plastics are generally considered be poor conductors of electricity.
However, the discovery in the 1970s that polymers can be made conductive
by manipulating their chemical structure has lead to the exciting
possibility of making ‘electronics on plastic’, with
associated advantages including mechanical flexibility, robustness,
chemical versatility, low weight, and most significantly low cost
and ease of large scale production. Already flexible organic display
technologies are in the marketplace and significant attention is
now being directed towards other organic electronic devices such
as transistors and solar cells. Presently much of the electronic
properties of these materials are still poorly understood.
In 2003 we continued to expand our new organic electronic devices
research program. Early in the year we completed the installation
of equipment for the first stage of our new laboratories. This equipment
includes a combined RF sputtering and thermal evaporation system,
a laminar flow cabinet with spin coater and a deionised water system.
In 2004 we will establish a cleanroom and wet chemistry lab for
In May, Dr Adam Micolich commenced an ARC Postdoctoral Fellowship
to explore the electronic properties of organic field-effect transistors
based on molecular crystals and thin-films. As part of this research,
Dr Ali Rashid joined our interdisciplinary group in late 2003 to
lead the chemistry side of the program, bringing experience in synthesis
and the growth of organic molecular crystals. We hope to measure
our first samples in 2004.
Our second new project in organic solar cells, with Dr Neil Kemp
and A/Prof Richard Newbury, is to explore how polymer/C60 blends
can be optimized to increase their photovoltaic efficiency. This
project extends on their preliminary work to investigate methods
for engineering the morphology of conducting polymers at the nanoscale
to improve charge conduction and increase the surface area for exciton
dissociation in conducting polymer/C60 fullerene photovoltaic devices.
Finally, an existing collaboration between Dr Adam Micolich, A/Prof
Alex Hamilton and Dr Paul Meredith’s group at the University
of Queensland has continued, with a series of measurements on the
electronic properties of ion-implanted plastics. In two series of
low-temperature measurements, we began characterizing the crossover
between metallic and insulating behaviour as a function of various
implant and material properties.
Anthony Tedesco, Neil Kemp, Ali Rashid,
Jack Cochrane, Alex Hamilton,
Adam Micolich and Richard Newbury