Influence of tantalum concentrations on the magnetic properties of amorphous CoFeTaB thin-films

Abstract The structural and magnetic properties of amorphous CoFeTaB thin-films were studied as a function of tantalum concentration. The investigations of the structural properties of amorphous CoFeTaB thin-films were undertaken to confirm layer thickness, interface roughness, and their amorphous structure. Temperature dependent magnetic characterizations were performed in order to extract Curie temperatures and their saturation magnetizations of each structure. Curie temperatures and saturation magnetizations of amorphous CoFeTaB thin-films show similar behaviour, where both quantities decrease with increasing tantalum concentration in thin-film structures. These reductions can be attributed to a result of a transfer of electrons from the metalloid atoms to the unfilled d holes of the 3d transition metals, and diffusion of tantalum atoms towards the ferromagnetic layer during thin-film deposition. Investigation of tuning both Curie temperature and magnetization by the addition of a non-magnetic transition metal is crucial for the development of spintronic applications.