| 摘要 |
PROBLEM TO BE SOLVED: To prevent ruggedness from occurring when an identification mark is given on a non-recording area, to prevent unstable flying of a head and head crush, etc., when a magnetic head is driven caused according to the formation of the identification mark and to provide the disk suitable for high density recording formation. SOLUTION: This disk is constituted so that a substrate 7, a magnetic layer and a protective layer are formed successively on a substrate, and the identification mark is given on the non-recording area. In such a case, the identification mark is within the range of 1-100nm in a height of a projection 9, and mean value of area of a figure surrounded by a contour at a height below 1nm from the peak of the projection is made 2μm<2> or below, and is formed by the projection 9 formed on any one of a non-magnetic substrate, the substrate 7, the magnetic layer or the protective layer.
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