M�ssbauer study of Fe magnetic state at the interface between Fe-Al-Si thin films and crystallized glass substrate

The magnetic state of Fe atoms at or near the interface between Fe74.3Al9.8Si15.9 sendust magnetic thin films and SiO2-based crystallized glass substrate (Fotoceram, Corning Co.) has been examined using conversion electron Mossbauer spectroscopy. The thicknesses of sputtered films are 0.05–2.0 Μm, and annealing conditions are at 500 ‡C for 1 H. The excellent soft magnetic properties are not obtained for films with a thickness of less than 0.5 Μm. The presence of ferromagnetic Fe atoms with internal magnetic fields of 24.3–24.9 MAm−1 is confirmed at or near the interface, indicating the formation of an Fe-rich phase such as Fe90Si10. The fraction of Fe atoms forming the Fe-rich phase at or near the interface is estimated to be around 20.... The formation of the Fe-rich phase is one of the main reasons for the degradation of the soft magnetic properties of sendust films deposited on SiO2-based crystallized glass substrate, even though the DO3-type ordered structure has also been formed.