| 摘要 |
PURPOSE:To lower a curie temperature and to enable recording and reproducing by semiconductor laser light maintaining reasonably high coercive force required for a memory by substituting part of the Fe atoms in a metal oxide of M-type ferrite with Al and M atoms. CONSTITUTION:A metal oxide magnetic material is shown by Formula I (wherein, Me=Ba, Sr and/or Pb, M=Ga, Co, Bi, Mn, Gd, Tb, Ho, Dy, La, Cr, Si, Cu, Y, Ge, V, Yb, Ta, Sb or Eu, 0.5<=X+Y<1.5, X>Y, 5<=n<=6, m is ion valence number of M). In order to make the metal oxide magnetic material, required quantity of BaCO3, SrCO3 or PbCO3 (or PbO), Fe2O3, Al2O3 and M metal oxide respectively are mixed and ground, put in an appropriate shape metal mold for forming and then sintered at a temperature of 1,200-1,400 deg.C. In order to make a magnetic film using the metal oxide magnetic material, it also depends on a kind of substrate but generally, the magnetic material is coated to a target of film thickness approx. 0.1-10mum at a substrate temperature of 500-700 deg.C by vacuum deposition, sputtering or ion plating. |
