Granted Patent B1

US 8,867,322 · App. 13/932,348 · Granted Oct 21, 2014

Abstract

Claims (70)

1. A medium for heat assisted magnetic recording, the medium comprising:

a substrate;

a heat sink layer on the substrate;

a thermal barrier bilayer on the heat sink layer, the thermal barrier bilayer comprising:

a first thermal barrier layer on the heat sink layer, and

an amorphous underlayer on the first thermal barrier layer; and

a magnetic recording layer on the amorphous underlayer,

wherein a thermal conductivity of the first thermal barrier layer is less than a thermal conductivity of the amorphous underlayer.

2. The medium of claim 1 , wherein the thermal conductivity of the first thermal barrier layer is in a range of about 5 percent to about 25 percent of the thermal conductivity of the amorphous underlayer.

3. The medium of claim 1 , wherein the thermal conductivity of the first thermal barrier layer is about 10 percent of the thermal conductivity of the amorphous underlayer.

4. The medium of claim 1 , wherein the first thermal barrier layer is about transparent and comprises at least one material different from a material of the amorphous underlayer.

5. The medium of claim 1 , wherein the first thermal barrier layer comprises an amorphous material.

6. The medium of claim 5 , wherein the first thermal barrier layer comprises amorphous carbon.

7. The medium of claim 1 , wherein the thermal barrier bilayer is configured to:

facilitate a heat transfer from the magnetic recording layer to the heat sink layer; and

impede a heat transfer from the heat sink layer to the magnetic recording layer.

8. The medium of claim 1 , wherein the first thermal barrier layer is deposited using a deposition sub-process comprising application of a bias voltage to the substrate.

9. The medium of claim 8 , wherein the deposition sub-process is selected from the group consisting of a chemical vapor deposition sub-process and a sputter deposition sub-process.

10. The medium of claim 1 , wherein the amorphous underlayer comprises a material selected from the group consisting of CrTiX, CrTaX, NiTaX, CoCrTaZrX, CoFeZrBCrX, CoTaZrX, CoFeTaZrX, CoCrWTaZrX, CoCrMoTaZrX, CoZrWMoX, and combinations thereof, wherein X is selected from the group consisting of SiO2 and ZrO2.

11. The medium of claim 1 , further comprising:

an adhesion layer between the substrate and the heat sink layer;

a growth layer between the amorphous underlayer and the magnetic recording layer; and

an overcoat layer on the magnetic recording layer.

12. The medium of claim 11 :

wherein the substrate comprises a material selected from the group consisting of an Al alloy, NiP plated Al, glass, glass ceramic, and combinations thereof;

wherein the adhesion layer comprises a material selected from the group consisting of CrTi, CrTa, NiTa, CoCrTaZr, CoFeZrBCr, CoTaZr, CoFeTaZr, CoCrWTaZr, CoCrMoTaZr, CoZrWMo, and combinations thereof;

wherein the heat sink layer comprises a material selected from the group consisting of Ag, Al, Au, Cu, Cr, Mo, Ru, W, CuZr, MoCu, AgPd, CrRu, CrV, CrW, CrMo, CrNd, NiAl, NiTa, and combinations thereof;

wherein the first thermal barrier layer comprises a material selected from the group consisting of C, Al2O3, SiO2, WO3, Ta2O5, Nb2O5, ZrO2, SiN, and combinations thereof;

wherein the amorphous underlayer comprises a material selected from the group consisting of CrTiX, CrTaX, NiTaX, CoCrTaZrX, CoFeZrBCrX, CoTaZrX, CoFeTaZrX, CoCrWTaZrX, CoCrMoTaZrX, CoZrWMoX, and combinations thereof, wherein X is selected from the group consisting of SiO2 and ZrO2;

wherein the growth layer comprises a material selected from the group consisting of Cr, Mo, NiAl, MgO, TiC, TiN, Ag, CrMo, Pt, Pd, Ru, and combinations thereof;

wherein the magnetic recording layer comprises a material selected from the group consisting of FePt, CoPt, and combinations thereof; and

wherein the overcoat layer comprises C.

13. A heat assisted magnetic recording system comprising:

the medium of claim 1 ;

a light source configured to direct light energy on to the medium; and

a magnetic transducer configured to write information to the medium.

14. 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 a thermal barrier bilayer on the heat sink layer comprising:

providing a first thermal barrier layer on the heat sink layer, and

providing an amorphous underlayer on the first thermal barrier layer; and

providing a magnetic recording layer on the amorphous underlayer,

wherein a thermal conductivity of the first thermal barrier layer is less than a thermal conductivity of the amorphous underlayer.

15. The method of claim 14 , wherein the thermal conductivity of the first thermal barrier layer is in a range of about 5 percent to about 25 percent of the thermal conductivity of the amorphous underlayer.

16. The method of claim 14 , wherein the thermal conductivity of the first thermal barrier layer is about 10 percent of the thermal conductivity of the amorphous underlayer.

17. The method of claim 14 , wherein the first thermal barrier layer is about transparent and comprises at least one material different from a material of the amorphous underlayer.

18. The method of claim 14 , wherein the first thermal barrier layer comprises an amorphous material.

19. The method of claim 18 , wherein the first thermal barrier layer comprises amorphous carbon.

20. The method of claim 14 , wherein the thermal barrier bilayer is configured to:

facilitate a heat transfer from the magnetic recording layer to the heat sink layer; and

impede a heat transfer from the heat sink layer to the magnetic recording layer.

21. The method of claim 14 , wherein providing the first thermal barrier layer on the heat sink layer comprises:

applying a bias voltage to the substrate; and

depositing the first thermal barrier layer on the heat sink layer using a deposition sub-process.

22. The method of claim 21 , wherein the deposition sub-process is selected from the group consisting of a chemical vapor deposition sub-process and a sputter deposition sub-process.

23. The method of claim 14 , wherein the amorphous underlayer comprises a material selected from the group consisting of CrTiX, CrTaX, NiTaX, CoCrTaZrX, CoFeZrBCrX, CoTaZrX, CoFeTaZrX, CoCrWTaZrX, CoCrMoTaZrX, CoZrWMoX, and combinations thereof, wherein X is selected from the group consisting of SiO2 and ZrO2.

24. The method of claim 14 , further comprising:

providing an adhesion layer between the substrate and the heat sink layer;

providing a growth layer between the amorphous underlayer and the magnetic recording layer; and

providing an overcoat layer on the magnetic recording layer.

25. The method of claim 24 :

wherein the substrate comprises a material selected from the group consisting of an Al alloy, NiP plated Al, glass, glass ceramic, and combinations thereof;

wherein the adhesion layer comprises a material selected from the group consisting of CrTi, CrTa, NiTa, CoCrTaZr, CoFeZrBCr, CoTaZr, CoFeTaZr, CoCrWTaZr, CoCrMoTaZr, CoZrWMo, and combinations thereof;

wherein the heat sink layer comprises a material selected from the group consisting of Ag, Al, Au, Cu, Cr, Mo, Ru, W, CuZr, MoCu, AgPd, CrRu, CrV, CrW, CrMo, CrNd, NiAl, NiTa, and combinations thereof;

wherein the first thermal barrier layer comprises a material selected from the group consisting of C, Al2O3, SiO2, WO3, Ta2O5, Nb2O5, ZrO2, SiN, and combinations thereof;

wherein the amorphous underlayer comprises a material selected from the group consisting of CrTiX, CrTaX, NiTaX, CoCrTaZrX, CoFeZrBCrX, CoTaZrX, CoFeTaZrX, CoCrWTaZrX, CoCrMoTaZrX, CoZrWMoX, and combinations thereof, wherein X is selected from the group consisting of SiO2 and ZrO2;

wherein the growth layer comprises a material selected from the group consisting of Cr, Mo, NiAl, MgO, TiC, TiN, Ag, CrMo, Pt, Pd, Ru, and combinations thereof;

wherein the magnetic recording layer comprises a material selected from the group consisting of FePt, CoPt, and combinations thereof; and

wherein the overcoat layer comprises C.

Assignments (10)