Scanning electron 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 device fabrication.

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