Magnetic recording media design with reduced lattice mismatch between adjacent intermediate layers
Magnetic recording media including an interlayer configured to reduce lattice mismatch with adjacent layers of the media, such as an adjacent seed layer or an adjacent underlayer. In one example, an interlayer alloy is provided that includes tungsten (W) along with Cobalt (Co), Chromium (Cr), and Ruthenium (Ru). The atomic percentages of W and Ru within the interlayer are selected so that the amount lattice mismatch between the interlayer and its adjacent layers is below a preselected amount, such as below 3% as quantified by d-spacing. In some examples, the atomic percentage of Ru is greater than 25% and the atomic percentage of W is 2-10%. Methods of fabricating the magnetic recording media are also provided.
1. A magnetic recording medium, comprising:
a substrate;
a seed layer on the substrate;
an interlayer on the seed layer, wherein the interlayer includes cobalt (Co), chromium (Cr), ruthenium (Ru) and an additional metal selected from a group consisting of tungsten (W), tantalum (Ta), molybdenum (Mo), and Niobium (Nb), and wherein the atomic percentage of the Ru within the interlayer is at least 25%;
an underlayer directly on the interlayer; and
one or more magnetic recording layers on the underlayer, wherein the one or more magnetic recording layers comprises perpendicular magnetic anisotropy.
2. The magnetic recording medium of claim 1 , wherein the interlayer comprises CoCrRuW with an atomic percentage of W in a range of 2% to 10%.
3. The magnetic recording medium of claim 2 , wherein the interlayer comprises Co50Cr23Ru25W2 or Co45Cr25Ru25W5.
4. The magnetic recording medium of claim 1 , wherein the underlayer comprises ruthenium (Ru).
5. The magnetic recording medium of claim 1 , wherein the seed layer comprises nickel (Ni), iron (Fe), tungsten (W), and aluminum (Al).
6. The magnetic medium of claim 1 , further comprising a soft underlayer (SUL), with the seed layer on the SUL and the SUL on the substrate.
7. The magnetic recording medium of claim 1 , wherein the one or more magnetic recording layers comprise Co-based magnetic layers with multiple exchange control sublayers (ECLs).
8. A data storage device comprising the magnetic recording medium of claim 1 .
9. The magnetic recording medium of claim 1 , wherein a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%.
10. A method for fabricating magnetic recording media, comprising:
providing a substrate;
providing a soft underlayer (SUL) on the substrate;
providing a seed layer on the SUL;
providing an interlayer on the seed layer, wherein the interlayer includes cobalt (Co), chromium (Cr), ruthenium (Ru) and an additional metal selected from a group consisting of tungsten (W), tantalum (Ta), molybdenum (Mo), and Niobium (Nb), and wherein the atomic percentage of the Ru within the interlayer is at least 25%;
providing an underlayer directly on the interlayer; and
providing one or more magnetic recording layers on the underlayer, wherein the one or more magnetic recording layers comprises perpendicular magnetic anisotropy.
11. The method of claim 10 , wherein the interlayer comprises CoCrRuW with an atomic percentage of W in a range of 2% to 10%.
12. The method of claim 11 , wherein the interlayer comprises Co50Cr23Ru25W2 or Co45Cr25Ru25W5.
13. The method of claim 10 , wherein the underlayer comprises ruthenium (Ru).
14. The method of claim 10 , wherein providing the seed layer comprises providing the seed layer to comprise a lattice of nickel (Ni), iron (Fe), tungsten (W), and aluminum (Al).
15. The method of claim 10 , wherein providing the one or more magnetic recording layers comprises providing one or more Co-based magnetic layers with multiple exchange control sublayers (ECLs).
16. The method of claim 10 , wherein the interlayer is provided so that a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%.
17. A magnetic recording medium, comprising:
a seed layer;
an interlayer on the seed layer;
an underlayer directly on the interlayer; and
one or more magnetic recording layers on the underlayer, wherein the one or more magnetic recording layers comprises perpendicular magnetic anisotropy;
wherein the interlayer comprises cobalt (Co), chromium (Cr), ruthenium (Ru) and an additional metal selected from a group consisting of tungsten (W), tantalum (Ta), molybdenum (Mo), and Niobium (Nb), and wherein the atomic percentage of the Ru within the interlayer is at least 25%.
18. The magnetic recording medium of claim 17 , wherein the interlayer comprises CoCrRuW having an atomic percentage of W in a range of 2% to 10%.
19. The magnetic recording medium of claim 18 , wherein the interlayer comprises Co50Cr23Ru25W2 or Co45Cr25Ru25W5.
20. A data storage device comprising the magnetic recording medium of claim 17 .
21. The magnetic recording medium of claim 17 , wherein a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%.
22. The magnetic recording medium of claim 17 , wherein a percentage of the additional metal in the interlayer is selected to reduce a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer as compared to a corresponding lattice mismatch without the additional metal, and wherein the lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%.
23. A magnetic recording medium, comprising:
a substrate;
a seed layer on the substrate;
an interlayer on the seed layer, wherein the interlayer includes cobalt (Co), chromium (Cr), ruthenium (Ru) and an additional metal selected from a group consisting of tungsten (W), tantalum (Ta), molybdenum (Mo), and Niobium (Nb), and wherein the atomic percentage of the Ru within the interlayer is at least 25%;
an underlayer on the interlayer, wherein a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%; and
one or more magnetic recording layers on the underlayer, wherein the one or more magnetic recording layers comprises perpendicular magnetic anisotropy.
24. A magnetic recording medium, comprising:
a seed layer;
an interlayer on the seed layer;
an underlayer on the interlayer; and
one or more magnetic recording layers on the underlayer, wherein the one or more magnetic recording layers comprises perpendicular magnetic anisotropy;
wherein the interlayer comprises cobalt (Co), chromium (Cr), ruthenium (Ru) and an additional metal selected from a group consisting of tungsten (W), tantalum (Ta), molybdenum (Mo), and Niobium (Nb), wherein the atomic percentage of the Ru within the interlayer is at least 25%, wherein a lattice mismatch between the interlayer and one or both of the seed layer and the underlayer is no greater than 3%.