MAGNETIC-ORDERING IN AMORPHOUS OXIDES

The magnetic structure of radio frequency sputtered amorphous oxides h as been investigated by magnetization and ferromagnetic resonance tech niques. Samples of Bi2O3-Fe2O3 substituted with ABO3 (AB=BaTi, PbTi, P bZr) and MeO (Me=Cu, Ca, Zn) - type compounds have been studied. As-de posited samples are paramagnetic and samples annealed at high temperat ures show a ferrimagnetic character possibly due to the formation of m agnetically ordered clusters. Key accomplishments of our studies are: (i) samples with nonmagnetic ABO3 show a record room temperature magne tization, (ii) films containing oxides of zinc, copper, or calcium are anisotropic amorphous magnets with a large uniaxial or planar anisotr opy, (iii) the nature and composition of ordered clusters in some samp les have been inferred from magnetic characterization of the films, an d (iv) a similar ferrimagnetic character is observed in amorphous samp les sputtered at high temperatures.