Fe-implanted 6H-SiC: Direct evidence of Fe_3Si nanoparticles observed by atom probe tomography and ~(57)Fe Moessbauer spectroscopy

摘要

In order to understand ferromagnetic ordering in SiC-based diluted magnetic semiconductors, Fe-implanted 6H-SiC subsequently annealed was studied by Atom Probe Tomography, ~(57)Fe Moessbauer spectroscopy and SQUID magnetometry. Thanks to its 3D imaging capabilities at the atomic scale, Atom Probe Tomography appears as the most suitable technique to investigate the Fe distribution in the 6H-SiC host semiconductor and to evidence secondary phases. This study definitely evidences the formation of Fe_3Si nano-sized clusters after annealing. These clusters are unambiguously responsible for the main part of the magnetic properties observed in the annealed samples.