Retention and release of deuterium implanted in W and Mo

Retention and thermal release of deuterium implanted in W with various carb on contents were studied by ion beam analysis techniques. The correlation b etween implantation induced defects and deuterium trapping in W was examine d in comparison with that in Mo. The D concentration in the near surface la yer of the W crystal was higher than that in the Mo crystal during 10 keV D -2+ implantation at room temperature. In case of the D implanted Mo crystal , the isolated interstitial atoms were mainly recognized by the ion channel ing. On the other hand, a large lattice distortion caused by the extended d efects was observed in the near surface layer of the D implanted W at room temperature, and the distortion was not effectively formed above 390 K. The appreciable amount of the retained D atoms was released from pure W at aro und 450 K at which the lattice distortion was partly annealed out. The ther mal release of D retained in the carbon containing W abruptly occurred at a bout 350 K, independent of the carbon contents. (C) 1999 Elsevier Science I nc. All rights reserved.