题 目： Real-time Transmission Electron Microscopy Observation of Ion Irradiation of Solids
报告人：Huddersfield大学 S .E. Donnelly 教授
时 间：2011年12月13日（周二）10:00
地 点：材料楼210报告厅
【讲座摘要】
Transmission electron microscopy (TEM) offers the ability to image and analyse the internal microstructure of materials at high resolution. The combination of TEM with in-situ ion irradiation enables the build-up of radiation damage to be monitored as it develops, offering significant insights into the atomistics of defect nucleation and growth processes. By operating at low ion fluxes, radiation damage events due to individual ion effects can be studied in some systems. On the other hand, high-flux experiments offer the possibility of investigating the effects of high levels of atomic displacements on (for instance) potential nuclear reactor materials thus simulating, in relatively short periods, damage induced by neutron irradiation during many years of reactor operation. Studies using such facilities have relevance to applications not only in nuclear reactor materials but also in semiconductor processing, materials for use in space and in nanotechnology. The newest of these facilities, the MIAMI* Facility, was constructed at the University at Salford and has recently moved to the University of Huddersfield.
In the first part of the presentation, an overview will be provided of work carried out by the author and colleagues over the last decade using in-situ facilities at Argonne National Laboratory in the US and the National Institute for Materials Science in Japan. This will include studies of the effects of single-ion impacts on metal surfaces in which the existence of thermal spike effects was conclusively demonstrated; observations of the effects of atomic displacements on the behaviour of “bubbles” containing room temperature, solid Xe; and the amorphisation of silicon by heavy ions. In the second part of the presentation a description of the Huddersfield MIAMI facility will be given and a number of current projects on nuclear materials, semiconductors and nanomaterials will be briefly discussed.