Thickness dependence of the phase transformation in FePt alloy thin films

Abstract FePt alloy thin films of different thickness have been prepared and studied. Both X-ray analysis and magnetization measurements have been used to detect the FCC (A1)–FCT (L1 0 ) phase transformation due to annealing in these films. It was found that the ordering process in the thick samples takes place at much lower temperature in comparison to the thinner ones. The observed phenomenon can be understood taking into account the kinetics of the FCC–FCT phase transformation and grain growth. The obtained experimental results suggest the existence of an optimal annealing temperature for each defined sample thickness.