Stack including a magnetic zero layer

Patent metadata

Field	Value
Publication number	US-9093101-B2
Application number	US-201113037288-A
Country	US
Kind code	B2
Filing date	Feb 28, 2011
Priority date	Feb 28, 2011
Publication date	Jul 28, 2015
Grant date	Jul 28, 2015

Abstract

A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (B s ) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.

First claim

The invention claimed is:

1. A stack, comprising:
a crystallographic orientation interlayer;
a magnetic zero layer disposed on the interlayer, the magnetic zero layer being non-magnetic and comprising non-magnetic grains separated by a non-magnetic segregant; and
a magnetic recording layer disposed on the magnetic zero layer, the magnetic recording layer comprising ferromagnetic grains separated by a non-magnetic segregant, wherein the magnetic zero layer comprises the same elements as the magnetic recording layer, a percentage by volume of the non-magnetic segregant of the magnetic zero layer is greater than a percentage by volume of the non-magnetic segregant of the magnetic recording layer, a lattice mismatch between the interlayer and the magnetic recording layer is less than about 4%, and a thickness of the magnetic zero layer is less than about 10 Å.

2. The stack of claim 1 , wherein the segregant of the magnetic zero layer and the segregant of the magnetic recording layer comprise the same material.

3. The stack of claim 1 , wherein the magnetic zero layer comprises the same elements in different proportions as the magnetic recording layer.

4. The stack of claim 1 , wherein the segregant of the magnetic zero layer is an amorphous material.

5. The stack of claim 1 , wherein the magnetic zero layer comprises a Co alloy having between about 40 mol % and about 60 mol % Co.

6. The stack of claim 1 , wherein the segregant of the magnetic zero layer comprises an oxide material and the segregant of the magnetic recording layer comprises the oxide material.

7. The stack of claim 6 , wherein the magnetic zero layer comprises greater than about 5 mol % of the oxide material.

8. The stack of claim 6 , wherein the magnetic zero layer comprises greater than about 10 vol % of the oxide material.

9. The stack of claim 6 , wherein the magnetic zero layer comprises a greater percentage of the oxide material than the magnetic layer.

10. The stack of claim 1 , wherein the magnetic recording layer comprises a first magnetic layer adjacent the magnetic zero layer and a second magnetic layer separated from the first magnetic layer by an exchange break layer.

11. The stack of claim 1 , wherein the grains of the magnetic zero layer are columnar grains having an HCP crystalline structure and a (0001) growth direction.

12. The stack of claim 1 , wherein the stack including the magnetic zero layer has increased exchange decoupling when compared to a substantially similar stack that does not include the magnetic zero layer.

13. The stack of claim 1 , wherein the magnetic zero layer comprises one or more of Pt and Ru.

14. A method of making a stack, comprising:
depositing a magnetic zero layer on a crystallographic orientation interlayer, the magnetic zero layer being non-magnetic and comprising non-magnetic grains separated by a non-magnetic segregant; and
depositing a magnetic layer on the magnetic zero layer, the magnetic layer comprising ferromagnetic grains separated by a non-magnetic segregant, wherein the magnetic zero layer comprises the same elements as the magnetic recording layer, a percentage by volume of the non-magnetic segregant of the magnetic zero layer is greater than a percentage by volume of the non-magnetic segregant of the magnetic recording layer, a lattice mismatch between the interlayer and the magnetic layer is less than about 4%, and a thickness of the magnetic zero layer is less than about 10 Å.

15. The method of claim 14 , wherein the magnetic zero layer comprises CoCr- and one or more of Pt and Ru, the magnetic recording layer comprises a Co alloy, the segregant of the magnetic zero layer and the segregant of the magnetic recording layer comprises an oxide, and the magnetic zero layer comprises a higher percentage by volume of the oxide than the magnetic recording layer.

16. The method of claim 14 , wherein a difference between the full width half maximum (FWHM) of crystallographic rocking curves of the interlayer and the magnetic recording layer is less than about 0.35 degrees.

17. A stack, comprising:
a crystallographic orientation interlayer;
a magnetic zero layer disposed on the interlayer, the magnetic zero layer being non-magnetic and comprising grains separated by a non-magnetic segregant, the magnetic zero layer comprising a CoCr alloy having Cr less than 30 at %; and
a magnetic recording layer disposed on the magnetic zero layer, the magnetic recording layer comprising ferromagnetic grains separated by a non-magnetic segregant, wherein a lattice mismatch between the interlayer and the magnetic recording layer is less than about 4%, a composition of the magnetic recording layer is different from composition of the interlayer, and a percentage by volume of the non-magnetic segregant of the magnetic zero layer is greater than a percentage by volume of the non-magnetic segregant of the magnetic recording layer, and a thickness of the magnetic zero layer is less than about 10 Å.

18. The stack of claim 17 , wherein the CoCr alloy further includes one or more of Pt and Ru.

19. A stack, comprising:
a crystallographic orientation interlayer;
a magnetic zero layer disposed on the interlayer, the magnetic zero layer being non-magnetic and comprising non-magnetic grains separated by a non-magnetic segregant; and
a magnetic recording layer disposed on the magnetic zero layer, the magnetic recording layer comprising ferromagnetic grains separated by a non-magnetic segregant, wherein the magnetic zero layer comprises the same elements as the magnetic recording layer, a lattice mismatch between the interlayer and the magnetic layer is less than 4%, and the magnetic zero layer comprises a greater percentage by volume of the non-magnetic segregant than the magnetic recording layer, and a thickness of the magnetic zero layer is less than about 10 Å.

20. A stack, comprising:
a crystallographic orientation interlayer;
a magnetic zero layer disposed on the interlayer, the magnetic zero layer being non-magnetic and comprising grains separated by a non-magnetic segregant; and
a magnetic recording layer disposed on the magnetic zero layer, the magnetic layer comprising ferromagnetic grains separated by a non-magnetic segregant, wherein the magnetic zero layer comprises the same elements as the magnetic recording layer and the magnetic zero layer has a thickness less than 10 angstroms, a lattice mismatch between the interlayer and the magnetic recording layer is less than about 4%, and the magnetic zero layer has a thickness less than about 10 Å.

Assignees

• Kim Jai-Young
• Nolan Thomas P
• Kang Kyongha
• Wang Shoutao
• Nguyen Vincent D
• Hailu Abebe
• Chen Charles C
• Seagate Technology Llc

Inventors

• Kim Jai-Young
• Nolan Thomas P
• Kang Kyongha
• Wang Shoutao
• Nguyen Vincent D
• Hailu Abebe
• Chen Charles C

Classifications

• G11B5/7325

  Physics · mapped topic

• G11B5/82 Primary

  Disk carriers · CPC title

• G11B5/66

  the record carriers consisting of several layers · CPC title

• G11B5/737

  Physical structure of underlayer, e.g. texture · CPC title

• G11B5/851

  Coating a support with a magnetic layer by sputtering · CPC title