HAMR media structure with intermediate layer underlying a magnetic recording layer having multiple sublayers
View Patent ↗Segregants for magnetic recording layers and materials for intermediate layers underlying the magnetic recording layers are provided for improved heat assisted magnetic recording (HAMR) media. One such HAMR medium includes a substrate, a heat sink layer on the substrate, an underlayer on the heat sink layer, an intermediate layer of TiON, VON, CrON, TiOC, VOC, TiONC, and/or combinations thereof, on the underlayer, and a magnetic recording layer of FePt on the intermediate layer. The magnetic recording layer further includes three sublayers, each having a different segregant. The segregant of the first magnetic recording sublayer on the intermediate layer includes AgBN, AgCN, AgBNC, AgB 2 O 3 , AgMoO 3 , AgV 2 O 5 , B 2 O 3 , MoO 3 , V 2 O 5 , and/or combinations thereof.
1. A medium for heat assisted magnetic recording, the medium comprising:
a substrate;
a heat sink layer on the substrate;
an underlayer on the heat sink layer;
an intermediate layer on the underlayer, the intermediate layer comprising a material selected from the group consisting of: TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and combinations thereof; and
a magnetic recording layer on the intermediate layer, the magnetic recording layer comprising:
a first magnetic recording sublayer on the intermediate layer, the first magnetic recording sublayer comprising FePt with a first segregant, the first segregant comprising a material selected from the group consisting of: AgBN, AgCN, AgBNC, AgB 2 O 3 , AgMoO 3 , AgV 2 O 5 , B 2 O 3 , MoO 3 , V 2 O 5 , and combinations thereof,
a second magnetic recording sublayer on the first magnetic recording sublayer, the second magnetic recording sublayer comprising FePt with a second segregant different than the first segregant, and
a third magnetic recording sublayer on the second magnetic recording sublayer, the third magnetic recording sublayer comprising FePt with a third segregant different than the first segregant and the second segregant.
2. The medium of claim 1 , wherein the intermediate layer comprises TiO x N (1-x) , where x is between about 0.4 and about 0.5.
3. The medium of claim 1 , wherein the underlayer comprises a material selected from the group consisting of: TiN, CrN, VN, TiC, VC, RuAl, RuTi, FeAl, SrTiO 3 , BaTiO 3 , BaSnO 3 , MgO, W, Mo, Cr, NiAl, and combinations thereof.
4. The medium of claim 3 , wherein the underlayer comprises TiN.
5. The medium of claim 1 , wherein the first segregant comprises AgBN.
6. The medium of claim 5 , wherein the first segregant comprises a BN content between about 25 mole percent and about 40 mole percent.
7. The medium of claim 5 , wherein the intermediate layer comprises TiON.
8. The medium of claim 1 , wherein the second segregant comprises a material selected from the group consisting of: BNC, BN, and combinations thereof.
9. The medium of claim 1 , wherein the third segregant comprises a material selected from the group consisting of: BNSiO 2 , BNZrO 2 , BNTa 2 O 5 , and combinations thereof.
10. The medium of claim 1 , wherein the heat sink layer comprises a material selected from the group consisting of: W, Mo, Ru, Cr, Cu, Ag, Cu alloy, Ag alloy, and combinations thereof.
11. The medium of claim 1 , further comprising:
an adhesion layer on the substrate, the adhesion layer comprising a material selected from the group consisting of: CrTa, NiTa, and combinations thereof;
a seed layer on the adhesion layer, the seed layer comprising a material selected from the group consisting of: RuAl, Cr, and combinations thereof;
wherein the heat sink layer is on the seed layer.
12. The medium of claim 1 , wherein the intermediate layer is deposited using a reactive sputtering process in a mixture of Ar gas and O 2 gas.
13. The medium of claim 12 , wherein the mixture of Ar gas and O 2 gas comprises between about 1.6 percent O 2 and about 1.8 percent O 2 .
14. The medium of claim 1 , wherein the intermediate layer is deposited using a non-reactive sputtering process with a composite target comprising TiON.
15. A heat assisted magnetic recording system comprising:
the medium of claim 1 ;
a near-field transducer light source configured to direct light energy on to the medium; and
a magnetic transducer configured to write information to the medium.
16. A method for fabricating a medium for heat assisted magnetic recording, the method comprising:
providing a substrate;
providing a heat sink layer on the substrate;
providing an underlayer on the heat sink layer;
providing an intermediate layer on the underlayer, the intermediate layer comprising a material selected from the group consisting of: TiON, VON, CrON, TiOC, VOC, TiONC, VONC, and combinations thereof; and
providing a magnetic recording layer on the intermediate layer, the magnetic recording layer comprising:
a first magnetic recording sublayer on the intermediate layer, the first magnetic recording sublayer comprising FePt with a first segregant, the first segregant comprising a material selected from the group consisting of: AgBN, AgCN, AgBNC, AgB 2 O 5 , AgMoO 3 , AgV 2 O 5 , B 2 O 3 , MoO 3 , V 2 O 5 , and combinations thereof,
a second magnetic recording sublayer on the first magnetic recording sublayer, the second magnetic recording sublayer comprising FePt with a second segregant different than the first segregant, and
a third magnetic recording sublayer on the second magnetic recording sublayer, the third magnetic recording sublayer comprising FePt with a third segregant different than the first segregant and the second segregant.
17. The method of claim 16 , wherein the intermediate layer comprises TiO x N (1-x) , where x is between about 0.4 and about 0.5.
18. The method of claim 16 , wherein the underlayer comprises a material selected from the group consisting of: TiN, CrN, VN, TiC, VC, RuAl, RuTi, FeAl, SrTiO 3 , BaTiO 3 , BaSnO 3 , MgO, W, Mo, Cr, NiAl, and combinations thereof.
19. The method of claim 16 , wherein the underlayer comprises TiN.
20. The method of claim 16 , wherein the first segregant comprises AgBN.
21. The method of claim 20 , wherein the first segregant comprises a BN content between about 25 mole percent and about 40 mole percent.
22. The method of claim 20 , wherein the intermediate layer comprises TiON.
23. The method of claim 16 , wherein the second segregant comprises a material selected from the group consisting of: BNC, BN, and combinations thereof.
24. The method of claim 16 , wherein the third segregant comprises a material selected from the group consisting of: BNSiO 2 , BNZrO 2 , BNTa 2 O 5 , and combinations thereof.
25. The method of claim 16 , wherein the heat sink layer comprises a material selected from the group consisting of: W, Mo, Ru, Cr, Cu, Ag, Cu alloy, Ag alloy, and combinations thereof.
26. The method of claim 16 , further comprising:
providing an adhesion layer on the substrate, the adhesion layer comprising a material selected from the group consisting of: CrTa, NiTa, and combinations thereof;
providing a seed layer on the adhesion layer, the seed layer comprising a material selected from the group consisting of RuAl, Cr, and combinations thereof;
wherein the heat sink layer is on the seed layer.
27. The method of claim 16 , wherein providing the underlayer on the heat sink layer comprises:
depositing the underlayer using a sputtering process in substantially pure Ar gas.
28. The method of claim 27 , wherein providing the intermediate layer comprises:
depositing the intermediate layer on the underlayer using a reactive sputtering process in a mixture of Ar gas and O 2 gas.
29. The method of claim 28 :
wherein the underlayer comprises TiN; and
wherein the intermediate layer comprises TiO x N (1-x) , where x is between about 0.4 and about 0.5.
30. The method of claim 28 , wherein the mixture of Ar gas and O 2 gas comprises between about 1.6 percent O 2 and about 1.8 percent O 2 .
31. The method of claim 16 , wherein providing the intermediate layer comprises:
depositing the intermediate layer using a non-reactive sputtering process with a composite target comprising TiON.