Organic semiconductor devices such as organic solar cells and organic field-effect transistors are based on blended and/or multilayered structures. Many organic semiconductors used in high-performance devices are also semicrystalline or liquid crystalline with a complex relationship between film microstructure and device performance. Unravelling structure-function relationships in organic semiconductor devices therefore requires structural probes that have high chemical specificity, sensitivity to molecular orientation and order and high spatial resolution. Soft x-rays have proven to be versatile in spectroscopy, microspectroscopy and scattering experiments providing contrast derived from differences in the near-edge x-ray absorption spectra of different organic semiconductors. Furthermore, the sensitivity of polarised soft x-ray beams to the orientation of bonds in organic materials makes them a unique probe of molecular orientation. In this seminar I will provide an overview of the range of microscopy, reflectivity and scattering techniques based on soft x-rays that have been developed in recent years and their utility for providing new insight into the complex structure of organic semiconductor thin films.
Prof. Chris McNeill is Associate Professor and ARC Future Fellow in Monash University at the Department of Materials Engineering. In addition to his Future Fellowship, Dr McNeill is also the recipient of a Larkins Fellowship from Monash University and has previously been awarded a College Research Fellowship at Clare Hall, Cambridge, and an EPSRC Advanced Research Fellowship. Prof McNeill obtained a Bachelor of Mathematics, a Bachelor Science with Honours and a PhD at the University of Newcastle. Afterwards. he spent six years at the University of Cambridge, UK, as a Research Associate and an Engineering Physical Science Research Council (EPSRC) Advanced Research Fellow. Dr McNeill is currently engaged in research that aims to enable the development of a new generation of low-cost electronic device based on semiconducting plastics. Organic semiconductors offer the potential to realise inexpensive solar panels, flexible displays, energy efficient solid-state lighting and low-cost printed electronics that aim to make day-to-day life easier. His research interests include organic semiconductor device physics, polymer solar cells, organic field-effect transistors, structural properties of organic semiconductor films and synchrotron-based soft x-ray techniques.