Deuterium retention in tungsten and molybdenum

Trapping of D atoms implanted in W and Mo single crystals was investigated in connection with the implantation-induced defects by using ion beam analy sis techniques. The amount of the retained D atoms near the surface layer o f the W crystal was higher than of the Mo crystal at a temperature range be tween 300 and 650 K. Depth profile studies of the retained D atoms and defe cts indicated that trapping of D atoms implanted in the W and the Mo crysta l was associated with lattice distortion due to implantation-induced extend ed defects such as interstitial loops. The D atoms implanted in the W cryst al were found to be located near the tetrahedral interstitial site, both in the implant surface layer and in the greater depth where few displacements were expected to be created by collisions. (C) 2000 Elsevier Science B.V. All rights reserved.