Epitaxial growth of [111] oriented manganese zinc ferrite thin films and their magnetic properties

Manganese zinc ferrite (MnZn ferrite) thin films were prepared on quartz substrates buffered by a ZnO underlayer by rf magnetron sputtering. The ZnO underlayers exhibited preferentially [001] orientation for any thickness. When Mn-Zn-Fe oxide layers as-deposited on the ZnO underlayers were annealed in reduced atmosphere at 800/spl deg/C for 5 hours, single-phase spinel type ferrites were formed. The films were preferentially oriented to the [111] direction normal to the film plane. Thin ZnO underlayers successfully induced [111] orientation in plane because of good lattice matching between the ZnO and the spinel phase. Films with a composition of Mn:Zn:Fe=23:9:68 had a saturation magnetization value of 410 emu/cm/sup 3/. The relationship between the composition and the magnetization for the films was similar to that for the bulk material.