Insight into the co-deposition of deuterium with beryllium: Influence of the deposition conditions on the deuterium retention and release

A systematic study of the influence of the deposition conditions on the deuterium retention by and release from co-deposited beryllium layers has been carried out in PISCES-B. Experimental parameters such as the beryllium deposition rate, the incident particle energy and the substrate temperature are shown to affect the level of hydrogen isotope retention in the layers. In addition, the pressure during deposition and the presence of Ar in the plasma are monitored since they influence the layer morphology and the ease of fuel removal by thermal desorption. Consequences for both the tritium inventory and effectiveness of tritium removal during bake-out procedures in ITER will be discussed.