| 摘要 |
PURPOSE:To obtain high coercive force and a high square-shaped ratio by providing a metallic film of a Co-Pt alloy on the surface of a tape-shaped substrate and orienting the magnetization facilitating axis of the alloy provided within the surface of the substrate so as to be coincident with the lengthwise direction of the substrate. CONSTITUTION:A pair of targets 2 and 2 are produced by providing a prescribed amount of Pt pellet on an alloy plate containing cobalt and platinum mixed together in a prescribed ratio or on a cobalt substrate, i.e., the primary component of said alloy. A permanent magnet 21 which is magnetized in the direction as shown in the figure is backed to generate a DC magnetic field 5 between both targets 2 and 2. In addition, a power supply 6 is provided to apply the negative voltage to both targets. Then the RF voltage is applied to these two targets in the same phase and at the same level. A tape substrate 34 which is driven toward a reel 33 is set so that its lengthwise direction is coincident with the direction of the field 5. The direction of this field 5 is tilted in the lengthwise direction of a magnetic tape by an angle formed by a video track and said lengthwise direction, e.g., by about 5 deg. of the beta system. Thus the field 5 is coincident with the video track. |
