Field emission-type scanning electron microscope for examination of irradiated fuels

Yasuda, Ryo; Mita, Naoaki; Nishino, Yasuharu ; Nakata, Masahito; Nozawa, Yukio; Harada, Katsuya ; Kushida, Teruo; Amano, Hidetoshi

The Field Emission type Scanning Electron Microscope (FE-SEM), which is one of effective tools for observation of micr-structures, was installed at the Reactor Fuel Examination Facility (RFEF) in JAERI. The FE-SEM is equipped in a large shield vessel with remote handling systems to keep safety of operators and is modified to enable to manipulate high radioactive materials. The Energy Dispersive Spectrometer (EDS) with radiation-shielded collimators has been also equipped on the FE-SEM to determine element compositions of the observed material samples. Characterization tests were carried out using deposited gold film and Zircaloy cladding tubes with hydrides to confirm the machine performance after the modifications. In the results of the tests, high-resolution images without some noises and fogs were obtained with high magnification above 10,000. Those results show that the FE-SEM keeps the high performance after some improvements and modifications for shielding -rays and handling radioactive samples.