| 摘要 |
PURPOSE:To obtain recording and reproducing characteristics which have a large squareness ratio and large coercive force with regard to a recording medium having a metallic magnetic thin film on a discoid base, by rotating the substrate through a mask and selecting its revolving speed, and performing vapor-phase plating so that the metallic magnetic material provides magnetic anisotropy in a circumferential direction. CONSTITUTION:In a vacuum-deposition container 11, a nonmagnetic discoid base 13 is set to a circular holder 14. A vacuum-deposition source 18 containing a metallic magnetic material such as Co and Hi is placed under the substrate 13 with a mask 17 in between. The mask 17 consists of shielding parts 17a and 17b, coupling width parts 17c, and openings 17d. The base 13 is rotated as shown by an arrow at a selected revolving speed. The container is evacuated by vacuum pump 12, and the vacuum-deposiition source 18 is irradiated by an electron gun 19 to perform vapor-phase plating on the substrate 13 through the openings 17d of the turning mask 17, thus obtaining a metallic film 21. When the revolving speed is >=1,000rpm, magnetic anisotropy in a circumferential direction is obtained and the coerctive force exceeds 700 Oe to obtain a magnetic recording medium which has a >=75% squareness ratio. |
