Influence of Sputter Pressure on the Texture and Magnetic Properties of Barium Ferrite Thin Films.

Abstract: M-type barium ferrite thin films were deposited onto sapphire (00l) substrates by radio frequency magnetron sputtering. Columnar grains were formed on the surface of the films under lower sputter pressure with bubble magnetic domains, which is originated from high magnetocrystalline anisotropy of the film. Magnetic hysteresis loops agree with the change of the morphology, where in-plane and out-of-plane loops are quite different of the samples prepared under high sputtering pressures, while they are almost identical under low pressures. The influence of the sputtering pressure was understood by that with the increase of the pressure, resputtering of the film is hindered. Nucleation with c-axis normal to the film plane was enhanced. Thus samples prepared under low pressure have more acicular crystallites which have c-axis parallel to the film plane. [Copyright &y& Elsevier]