Influence of the deposition conditions on the optical, electrical and magnetic properties of sputtered Fe-Al sub 2 O sub 3 and Ni-Al sub 2 O sub 3 nanocermet films

We reveal the influence of the deposition conditions on the physical properties of cermet films made of nanometer sized magnetic metal ( mu not equal to mu sub 0 ) and alumina grains. The films were prepared by rf cosputtering under two typical base pressures (10 exp -6 an 10 exp -7 Torr), using either an argon plasma or an Ar + 10% hydrogen plasma under 6 x 10 exp -3 Torr. They present a wide range of compositions and thicknesses. Electron microprobe analysis, transmission electron microscopy and high energy electron diffraction were used to study their crystallographic and granular structure. We report the electrical dc conductivity, optical transmittivity with respect to wavlength, magnetization and ferromagnetic resonance as a function of the deposition conditions. These physical properties are governed to a large extent by oxidation of the metal.