New Microscope and Ion Accelerators for Materials Investigations (MIAMI-2) system at the University of Huddersfield

摘要

Radiation damage is a complex dynamic process with multiple atomic mechanisms interacting and competing to determine the end state of the material. Transmission electron microscopy (TEM) with in-situ ion irradiation allows direct observation of the microstructural evolution of a sample from the virgin to end state. A new TEM with in-situ ion irradiation has been established at the University of Huddersfield: the Microscope and Ion Accelerators for Materials Investigations (MIAMI-2) system. MIAMI-2 combines a 300 kV TEM with medium-energy 350 kV and low-energy 20 kV ion beamlines. Whilst the medium-energy beamline can be used for most species up to Au, the low-energy beamline is primarily designed for implanting light-ion species such as H and He. These can be used individually or mixed prior to entering the TEM allowing dual-ion-beam irradiation experiments to, for example, simulate the combined effects of displacement damage and the introduction of He from (n, alpha) nuclear reactions. The TEM can operate from 60-300 kV and is equipped with a 16 megapixel digital camera, an energy-filtered imaging system and an energy-dispersive X-ray spectrometer for elemental and chemical analysis. Sample temperature can be varied from -170 degrees C to 1300 degrees C and a gas injection system enables gaseous environments at pressures of up to 10(-2) mbar at the sample position. The new MIAMI-2 system is a powerful tool for the investigation of radiation damage in a wide range of materials which are exposed to irradiating environments either during processing and/or whilst in-service in areas including nuclear applications, nanotechnology, semiconductor processing and extraterrestrial environments.