Published online by Cambridge University Press: 21 February 2011
Highly Bi-substituted iron garnet films are prepared on glass and single crystal substrates by conventional rf diode sputtering. The chemical composition of the films, especially, BI concentration strongly depends on sputtering conditions such as Ar gas pressure. Polycrystalline film of (Dy, Bi)3 (Fe, Al or Ga)5 012 on the glass substrate is promising for MO storage applications; they are good in film quality, and exhibit good squareness in magnetic hysteresis loop due to a prominent stress-induced magnetic anisotropy normal to the film plane. The polycrystalline films have a serious problem of suffering from the media noise due to grain boundary, to which we propose counter measures. We also describe the sputter epitaxial growth of the highly Bi-substituted iron garnet films with high quality, and compare the properties of the film with those of the LPE films. We also presented magnetic and MO properties of Ce-substituted YIG epitaxial films containing a large amount of Ce which were synthesized first by us using the sputtering technique. Cerium prominently enhances Faraday rotation in YIG, which surpasses the enhancement by BI. Thus the sputtered iron garnet films are promising materials for MO storage in the next generation.