Deuterium accumulation in beryllium oxide layer exposed to deuterium atoms

Abstract

The interaction of deuterium atoms with beryllium TIP-30 was studied at temperatures of 340, 500 and 740 K. After D atom exposure, the depth distributions of deuterium atoms and molecules in Be were measured using combined Secondary Ion Mass Spectrometry (SIMS) and Residual Gas Analysis (RGA) methods. It was shown that deuterium is mainly accumulated in the oxide layer although long tails are also observed. Deuterium is retained in two states – atomic and molecular forms. The amount of trapped deuterium in samples decreases during the sample storage in vacuum or air at room temperature. The results were explained by the chemical bonding of D atoms in BeO oxide with beryllium hydroxide formation and the trapping of deuterium molecules in bubbles which are formed at growth defects in the oxide layer.