Magnetic recording medium and method of manufacturing the same
A magnetic recording medium includes a substrate, and a soft magnetic layer, a crystal orientation control layer, a magnetic recording layer, and a protective layer formed sequentially on the substrate. The magnetic recording layer includes at least one granular magnetic layer having a granular structure and a non-granular magnetic layer having a non-granular structure. The at least one granular magnetic layers includes a plurality of magnetic portions and a separation portion surrounding the magnetic portions. The separation portion has magnetic characteristics different from the magnetic characteristics of the magnetic portions. The non-granular magnetic layer is a continuous film.
1 . A magnetic recording medium, comprising:
a substrate; and
a soft magnetic layer, a crystal orientation control layer, a magnetic recording layer, and a protective layer formed sequentially on the substrate, wherein
the magnetic recording layer includes a granular magnetic layer having a granular structure and a non-granular magnetic layer having a non-granular structure, the granular magnetic layer including a plurality of magnetic portions and a separation portion surrounding the magnetic portions, the separation portion having magnetic characteristics different from magnetic characteristics of the magnetic portions, the non-granular magnetic layer being a continuous film.
2 . The magnetic recording medium of claim 1 , wherein the magnetic recording layer includes a plurality of granular magnetic layers and the non-granular magnetic layer.
3 . The magnetic recording medium of claim 2 , wherein
the plurality of granular magnetic layers include a first granular magnetic layer, a second granular magnetic layer, and a coupling layer of a nonmagnetic material provided between the first and second granular magnetic layers; and
the non-granular magnetic layer is provided on a side of the second granular magnetic layer opposite to the coupling layer.
4 . A method of manufacturing a magnetic recording medium, comprising:
depositing a soft magnetic layer and a crystal orientation control layer sequentially on a substrate;
depositing a granular magnetic layer having a granular structure on the crystal orientation control layer;
processing the granular magnetic layer to form a plurality of magnetic portions and a separation portion; and
depositing a non-granular magnetic layer and a protective layer sequentially on the granular magnetic layer.
5 . The method of claim 4 , wherein the processing the granular magnetic layer further includes:
forming a mask having a plurality of openings on the granular magnetic layer;
exposing, through the mask, the granular magnetic layer to an activated halogen-containing reactive gas, thereby forming the separation portion in the granular magnetic layer at a position corresponding to the plurality of openings, and forming the magnetic portions at positions corresponding to portions of the mask that are not the openings; and
removing the mask.
6 . The method of claim 4 , wherein the depositing a granular magnetic layer includes depositing a plurality of granular magnetic layers on the crystal orientation control layer, and the processing the granular magnetic layer includes processing the plurality of granular magnetic layers.
7 . The method of claim 4 , wherein the separation portion has magnetic characteristics different from magnetic characteristics of the magnetic portions.
8 . The method of claim 4 , wherein the non-granular magnetic layer is a continuous film.