Recording medium comprising laminated underlayer structures
View Patent ↗A perpendicular recording medium having an underlayer structure that improves the microstructural properties of the recording layer. A spacer layer is intercalated between the lower and upper hcp metal layers. This results in improvements in microstructure of the upper hcp metal layer and the recording magnetic layer, which in turn results in gains in recording media performance. Further, the thickness of the upper hcp metal layer can be reduced, thereby reducing the distance between the recording layer and the soft underlayer, providing further gains in recording media performance.
1. A recording medium, comprising:
a soft underlayer;
a seed layer formed above the soft underlayer;
a first layer of hexagonal closed packed (hcp) metal formed on the seed layer;
a second layer of hcp metal formed above the first layer of hcp metal;
a magnetic layer formed above the second layer of hcp metal; and
a spacer layer intercalated between the first and second layers of hcp metal, the spacer layer being formed directly on the first layer of hcp metal, the second layer of hcp metal being formed directly on the spacer layer,
wherein at least one of the first and second layers of hcp metal is constructed of RuX, where X is selected from a group consisting of Cr, Mn, V and Cu,
wherein the spacer layer is constructed of a metal oxide.
2. A recording medium as recited in claim 1 , wherein the spacer layer has a different chemical composition than the first and second layers of hcp metal.
3. A recording medium as recited in claim 1 , wherein the spacer layer has a thickness sufficient to inhibit coherent grain growth between the first and second layers of hcp metal.
4. A recording medium as recited in claim 1 , wherein a chemical nature of the spacer layer is such that an adatom mobility of the second layer of hcp metal formed thereon is increased.
5. A recording medium, comprising:
a first layer of hexagonal closed packed (hcp) metal;
a second layer of hcp metal formed above the first layer of hcp metal;
a magnetic layer formed above the second layer of hcp metal; and
a spacer layer intercalated between the first and second layers of hcp metal, the spacer layer being formed directly on the first layer of hcp metal, the second layer of hcp metal being formed directly on the spacer layer,
wherein the spacer layer is constructed of a metal oxide.
6. A recording medium as recited in claim 1 , wherein a thickness of the spacer layer is between about 0.2 and about 4 nanometers (nm).
7. A recording medium as recited in claim 1 , wherein the spacer layer is constructed of an amorphous metal, a bcc metal, or their alloys.
8. A recording medium as recited in claim 7 , wherein a thickness of the spacer layer is between about 0.2 and about 4 nanometers (nm).
9. A recording medium as recited in claim 7 , wherein the spacer layer is constructed of Cr.
10. A recording medium as recited in claim 1 , wherein at least one of the first and second layers of hcp metal is constructed of RU.
11. A recording medium, comprising:
a soft underlayer;
a seed layer formed above the soft underlayer;
a first layer of hexagonal closed packed (hcp) metal formed on the seed layer;
a second layer of hcp metal formed above the first layer of hcp metal;
a magnetic layer formed above the second layer of hcp metal; and
a spacer layer intercalated between the first and second layers of hcp metal, the spacer layer being formed on the first layer of hcp metal, the second layer of hcp metal being formed on the spacer layer,
wherein at least one of the first and second layers of hcp metal is constructed of RuX, where X is selected from a group consisting of Cr, Mn, V and Cu,
wherein the spacer layer is constructed of an amorphous metal alloy.
12. A recording medium as recited in claim 1 , wherein the hcp metal in the first layer is different than the hcp metal in the second layer.
13. A recording medium as recited in claim 12 , wherein the hcp metal is a different alloy in each of the first and second layers.
14. A recording medium as recited in claim 1 , wherein the hcp metal in the first layer is a substantially pure metal, wherein the hcp metal in the second layer is RuX.
15. A recording medium as recited in claim 1 , wherein the first layer of hcp metal is formed under low pressure, wherein the second layer of hcp metal is formed tinder high pressure.
16. A recording medium, comprising:
a soft underlayer structure;
a seed layer above the soft underlayer structure;
a first layer of hexagonal closed packed (hcp) metal formed on the seed layer;
a second layer of hcp metal formed above the first layer of hcp metal;
a magnetic layer formed above the second layer of hcp metal;
a spacer layer intercalated between the first and second layers of hcp metal,
wherein all portions of the soft underlayer structure are positioned tinder the first and second layers of hcp metals,
wherein at least one of the first and second layers of hcp metal is constructed of RuX, where X is selected from a group consisting of Cr, Mn, V and Cu,
wherein the spacer layer is constructed of an amorphous metal alloy.
17. A recording medium as recited in claim 16 , wherein a chemical nature of the spacer layer is such that an adatom mobility of the second layer of hcp metal formed thereon is increased.
18. A magnetic storage system, comprising:
magnetic media having a structure as recited in claim 1 ;
at least one head for reading from and writing to the magnetic media, each head having:
a sensor; and
a write element coupled to the sensor;
a slider for supporting the head; and
a control unit coupled to the head for controlling operation of the head.
19. A recording medium as recited in claim 16 , wherein the spacer layer has a thickness sufficient to inhibit coherent grain growth between the first and second layers of hcp metal.
20. A recording medium , comprising:
a first layer of hexagonal closed packed (hcp) metal;
a second layer of hcp metal formed above the first layer of hcp metal;
a magnetic layer formed above the second layer of hcp metal; and
a spacer layer intercalated between the first and second layers of hcp metal,
wherein the spacer layer has a different chemical composition than the first and second layers of hcp metal,
wherein the spacer layer has a thickness sufficient to inhibit coherent grain growth between the first and second layers of hcp metal,
wherein a chemical nature of the spacer layer is such that an adatom mobility of the second layer of hcp metal formed thereon is increased,
wherein the spacer layer is constructed of a metal oxide selected from a group consisting of Ta 2 O 5 , SiO 2 and MgO.
21. A recording medium as recited in claim 16 , wherein the spacer layer is constructed of an amorphous metal, a bcc metal, or their alloys, wherein a chemical nature of the spacer layer is such that an adatom mobility of the second layer of hcp metal formed thereon is increased.
22. A recording medium as recited in claim 16 , wherein at least one of the first and second layers of hcp metal is constructed of Ru.
23. A recording medium as recited in claim 16 , wherein the hcp metal in the first layer is different than the hcp metal in the second layer.
24. A recording medium as recited in claim 16 , wherein the hcp metal in the first layer is a substantially pure metal, wherein the hcp metal in the second layer is RuX.
25. A magnetic storage system, comprising:
magnetic media having a structure as recited in claim 16 ;
at least one head for reading from and writing to the magnetic media, each head having:
a sensor; and
a write element coupled to the sensor;
a slider for supporting the head; and
a control unit coupled to the head for controlling operation of the head.
26. A recording medium as recited in claim 6 , wherein the metal oxide is selected from a group consisting of Ta 2 O 5 , SiO 2 and MgO.