VERTICAL MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To improve the squareness ratio and coercive force of a magnetic layer consisting of a magnetoplumbite type hexagonal ferrite and to improve the recording characteristic thereof by adding an element which is not substitutive with the iron atoms of the ferrite into said magnetic layer. CONSTITUTION:An underlying layer 13 and the magnetic layer 15 are laminated on a substrate 11 and the layer 15 is constituted mainly on the magnetoplumbite type hexagonal ferrite. The element which is substantially not substitutive with the iron atoms of the ferrite is incorporated in the form of metal or oxide therein. The layer 15 is formed by mixing the magnetoplumbite type hexagonal ferrite powder and the powder of the additive metal or oxide, sintering the mixture to form a target and sputtering the target in the case of a sputtering method. The squareness ratio of the magnetic layer is thereby improved and the recording characteristic is improved.