Deuterium in He-implanted Fe: Trapping and the surface permeation barrier

Abstract

Deuterium (D) and He were ion-implanted into Fe, and the D depth distribution was monitored during linear ramping of temperature. Defects associated with He, possibly small bubbles, were observed to trap the D with an enthalpy of 0.75±0.07 eV. The previously air-exposed Fe surface was a substantial permeation barrier to D: data analysis yielded a recombination coefficient of 10−18±0.7 cm4/sec at 500 K.