PURPOSE: To obtain an excellent photomagnetic recording medium for high density recording by having a vertically magnetized film having large coercive force and a magnetic layer having the magnetooptic Kerr rotational angle and reflectivivy both or either one of which is larger than both or either one of the magnetooptic Kerr rotational angle or refelectivity of the magnetic film on a base plate.
CONSTITUTION: The last magnetic layer 2 which is a vertically magnetized film having Curie temp. or a suitable magnetic compensating temp. and large coercive force is formed relatively thickly (about 1,000W5,000) by sputtering amorphous rare earth and transition metal or the like on a base plate 1 consisting of glass or polymethyl methacrylate, etc. The 2nd magnetic layer 3 which has the concn. of the transition metal higher than said concn. than the layer 2 and of which the codes of magnetical coupling and magnetooptic Kerr rotational angle θK are the same and the θK is larger or either is larger than that of the layer 2 is formed in single or multiple layers on the layer 2 by a sputtering method to the thickness over the entire part smaller than the intrusion distance of light. A transparent dielectric film 4 consisting of SiO2, MgF2, etc. is finally provided as a protective layer on the layer 3. The layer 3 consisting essentially of GdTbCoFe is preferred. The photothermomagnetic recording medium having low writing power and high bit stability is thus obtd.
SHIBATA TSUGIO
ARIMUNE HISAO
KYOCERA CORP
| JPS56153546A | 1981-11-27 | |||
| JPS58153244A | 1983-09-12 | |||
| JPS58145603A | 1983-08-30 |