Research interests

RESEARCH (a) Semiconductors: Defects in semiconductors and the characterisation of novel materials and structures constitute the main research area. The importance of defects lies in their pivotal role in the operation of devices, either as the basis of their operation or as major reasons for device failure. Understanding the detailed properties of atom-scale defects is the objective of our work so that we may better exploit the materials or compensate for their negative effects. There are two main strands to this research at this time. Radioactive isotopes are used to provide chemical identification of impurities in bulk semiconductors and to study the evolution of defects as elements transform from one to another. The high quality facilities in our laboratories are also used for the study of thin film semiconductor structures grown using a variety of novel techniques. The topics studied range from impurity and defect analysis in bulk silicon to the study of quantum dots in group IV and III-V materials and the analysis of wide bandgap semiconductors grown using pulsed laser deposition. Much of this work is carried out at very low temperatures where the material properties of the semiconductor are most clearly revealed. Facilities include high performance spectrometers, a high field superconducting magnet and an excellent range of cryogenic equipment. Current projects: (i) The use of radioactive isotopes for the study of impurity centres in semiconductors (international collaboration based in CERN at the ISOLDE facility) from1997-date (ii) Structural and electronic defect/dislocation characterisation in wide bandgap semiconductors (iii) The properties of zinc oxide nanostructures. (b) Physics Education: The focus of the work is the use of modern familiar technology (digital cameras, mobile phones, ipods) e for school laboratories, which seems to provide very positive stimuli to pupils towards science and to improve significantly their understanding of the concepts and the mathematical analysis.