electron microscopy techniques
convergent beam electron diffraction
Areas of expertise
My interests lie in the application of novel electron microscopy techniques to the analysis of defects and interfaces, particularly in semiconductors, to clarify microstructure/property relationships. My present research includes the development of new materials for field emission displays and solar cells, and studies of the role of defects in GaN light-emitting structures. In the latter, we have used transmission electron microscopy to analyse threading defects including dislocations, nanopipes and inversion domains. We have demonstrated, for the first time, that electron holography can be used to profile piezoelectric fields across InGaN quantum wells and around dislocations, and have used cathodoluminescence in a field-emission scanning electron microscope to examine the effects of individual threading defects on light emission.