Fabrication of insulator coatings for fusion reactor liquid lithium blankets Original Research Article

The development of insulating coatings is one of the most important subjects in fusion reactor liquid lithium blanket research and development. The compounds AlN, Y2O3 and Er2O3 are thought to be candidate materials for ceramic coatings because of their high electrical resistance and their high compatibility with liquid lithium. In this study, the coatings of these compounds were fabricated by the RF sputtering method, and their properties, thickness, composition ratio, impurities, crystallinity and resistivity were investigated. The coatings were polycrystalline and almost stoichiometric. Although the apparent resistivity data were scattered with different kinds of electrodes in the measurement, the coatings had enough high resistivity. After annealing, the crystallinity of the coatings became higher, but some cracks were observed on the surface of Y2O3 and Er2O3 coatings.