Perpendicular magnetic recording medium
A perpendicular magnetic recording medium includes a magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer. A non-magnetic orientation controller layer extends on the surface of the magnetic orientation controller layer The non-magnetic orientation controller layer serves as a layer for controlling crystalline orientation in an upper layer. A magnetic recording layer extends on the surface of the non-magnetic orientation controller layer. The perpendicular magnetic recording medium allows a reliable establishment of a uniform crystalline orientation in the magnetic recording layer based on the influences from the magnetic and non-magnetic orientation controller layers. A reliable establishment of a uniform crystalline orientation can be achieved without an increase in the thickness of the non-magnetic orientation controller layer.
1 . A perpendicular magnetic recording medium comprising:
a magnetic orientation controller layer including crystalline grains located adjacent each other, said magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer;
a non-magnetic orientation controller layer extending on a surface of the magnetic orientation controller layer and including crystalline grains located adjacent each other, said non-magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer; and
a magnetic recording layer extending on a surface of the non-magnetic orientation controller layer and including crystalline grains growing from the crystalline grains in the non-magnetic orientation controller layer.
2 . The perpendicular magnetic recording medium according to claim 1 , further comprising a soft magnetic underlayer spaced from the magnetic recording layer across the magnetic and non-magnetic orientation controller layers.
3 . The perpendicular magnetic recording medium according to claim 2 , wherein the crystalline grains in said magnetic recording layer have a hexagonal close-packed structure, while the crystalline grains in the magnetic orientation controller layer have a face-centered cubic structure.
4 . The perpendicular magnetic recording medium according to claim 3 , wherein (111) planes of the crystalline grains are preferentially oriented in parallel with a substrate in the magnetic orientation controller layer.
5 . The perpendicular magnetic recording medium according to claim 1 , wherein said crystalline grains in the magnetic recording layer have L 1 0 structure, while the crystalline grains in the magnetic orientation layer has a cubic structure.
6 . The perpendicular magnetic recording medium according to claim 5 , wherein (100) planes of the crystalline grains are preferentially oriented in parallel with a substrate in the magnetic orientation controller layer.
7 . The perpendicular magnetic recording medium according to claim 1 , wherein said crystalline grains in the magnetic recording layer have L 1 0 structure, while the crystalline grains in the magnetic orientation layer has a tetragonal structure.
8 . The perpendicular magnetic recording medium according to claim 7 , wherein (001) planes of the crystalline grains are preferentially oriented in parallel with a substrate in the magnetic orientation controller layer.
9 . The perpendicular magnetic recording medium according to claim 1 , wherein the magnetic orientation controller layer includes at least one of Fe, Co and Ni.
10 . The perpendicular magnetic recording medium according to claim 9 , wherein the magnetic orientation controller layer includes at least one element selected from a group consisting of Mo, Cr, Cu, V, Nb, Al, Si and B.
11 . The perpendicular magnetic recording medium according to claim 10 , further comprising a basement layer receiving the magnetic orientation controller layer.
12 . The perpendicular magnetic recording medium according to claim 11 , wherein said basement layer includes at least one element selected from a group consisting of Ta, C, Mo, Ti, W, Re, Os and Hf.
13 . A multilayered structure film comprising:
a magnetic orientation controller layer including crystalline grains located adjacent each other, said magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer;
a non-magnetic orientation controller layer extending on a surface of the magnetic orientation controller layer and including crystalline grains located adjacent each other, said non-magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer; and
a crystalline layer extending on a surface of the non-magnetic orientation controller layer and including crystalline grains growing from the crystalline grains in the non-magnetic orientation controller layer.