Deuterium thermal desorption experiments were performed on 132 FeAl thin films deposited by electron-beam evaporation on Si substrates, annealed at temperatures ranging from 673 to 773 K and implanted with 20 keV D-2 ions at fluences of 3 x 10(16) D(2)(+)cm(-2). D-2 desorption spectra, recorded in isochronal heating conditions (0.5 K s(-1) temperature ramp), show two well resolved desorption peaks at -500 and 820 K. The first peak is attributed to the desorption of deuterium contained in FeAl weakly bonding sites of the FeAl lattice, probably point defects (vacancies) produced by the ion implantation process. The second peak is attributed to deuterium release from trapping sites in the FeAl lattice that could be the defect complexes formed by the association of a vacancy in the Fe sublattice and a substitutional Fe atom in the Al sublattice (V-Fe-Fe-Al). The desorption kinetics can be reproduced by assuming that: (a) deuterium desorption at -500 K is controlled by the D2 surface recombination process with E-des = 1.57 +/- 0.02 eV as activation energy; (b) deuterium desorption at similar to820 K is controlled by the release of D atoms from the trap sites, a process which occurs in connection with defect relaxation. The energy of interaction of deuterium with this trapping site can be estimated to be similar to2 eV. [References: 52]
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