Study on high dose iron ion implantation in aluminum foil

Iron was implanted to different implantation doses (1×1017–1×1018 cm−2) at different average beam fluxes (25–76 μA cm−2) in high purity aluminum foil by using a metal vapor vacuum arc ion implanter. The maximum thickness of the implanted layer can range between 350 and 400 nm for the highest dose of 1×1018 cm−2. Upon implantation dose and average beam flux, the retained concentration of Fe implants ranges between 22 at.% and lower than 10 at.%. Two crystal phases, i.e. Fe2Al5 and FeAl6, are formed in the samples which were implanted to a dose larger than or equal to 5×1017 cm−2 at an average beam flux of 51 μA cm−2. The ratio of Fe2Al5 to FeAl6 increases with increasing implantation dose and average beam flux. The effect of implantation conditions on Mössbauer parameters is given. Mössbauer measurement reveals that there exists an amorphous state in the specimen implanted to the lowest implantation dose of 1×1017 cm−2 at the smallest average beam flux of 25 μA cm−2.