| 摘要 |
PURPOSE:To improve the S/N without reducing the reproduced output, by providing a ruthenium-plated layer between a nonmagnetic substrate and a foundation layer plated with a nickel alloy. CONSTITUTION:A ruthenium-plated layer 5 is formed on a nonmagnetic substrate 1 of aluminum alloy, etc., and a nickel alloy plated layer 2 is formed on the layer 5. Furthermore a cobalt alloy-plated layer 3 and then a protecting film 4 are formed on the layer 2. With formation of the layer 5, the effect of the substrate is cut off while maintaining the magnetic characteristics of a magnetic thin film. Thus a high output is attained with a low level of noise. |
