Analysis of deuterium in V–Fe5at.% film by atom probe tomography (APT)

V–Fe5at.% 2 and 10-nm thick single layered films were prepared by ion beam sputtering on W substrate. They were loaded with D from gas phase at 0.2 Pa and at 1 Pa, respectively. Both lateral and depth D distribution of these films was investigated in detail by atom probe tomography. The results of analysis are in good agreement between the average deuterium concentration and the value, expected from electromotive force measurement on a similar flat film. An enrichment of deuterium at the V/W interface was observed for both films. The origin of this D-accumulation was discussed in respect to electron transfer, mechanical stress and misfit dislocations.

Research highlights▶ Deuterium distribution in V–Fe thin film was investigated by atom probe tomography. ▶ Correct analysis was possible at analysis temperatures below 30 K. ▶ Inhomogeneous distribution of D atoms was nevertheless observed. ▶ This was interpreted by trapping effect at misfit dislocation. ▶ Atom probe analysis provides detailed information on local chemistry of M-D system.