Magnetic thin film media with a pre-seed layer of CrTiAl
View Patent ↗The applicants disclose a thin film magnetic media structure with a pre-seed layer of CrTiAl. The CrTiAl pre-seed layer presents an amorphous or nanocrystalline structure. The CrTiAl pre-seed layer improves in-plane c-axis orientation while maintaining a good orientation ratio. The pulse transition width (PW50) is narrowed and the soft error rate is improved. The preferred seed layer is RuAl.
1. A thin film layer structure for use in magnetic recording comprising:
a pre-seed layer of CrTiAl having an amorphous structure;
at least one seed layer above the pre-seed layer;
at least one underlayer above the seed layer; and
at least one magnetic layer above the underlayer.
2. The thin film structure of claim 1 wherein the seed layer is RuAl having a B2 crystallographic structure.
3. The thin film layer structure of claim 1 wherein the pre-seed layer of CrTiAl is approximately 5 to 20 at. % aluminum.
4. The thin film layer structure of claim 1 wherein the pre-seed layer of CrTiAl is deposited on a circumferential textured nonmetallic substrate.
5. A magnetic thin film storage medium comprising:
a substrate;
a layer of CrTiAl deposited on the substrate, the CrTiAl having an amorphous or nanocrystalline structure;
a layer of RuAl over the layer of CrTiAl; and
at least one underlayer over the layer of RuAl
at least one magnetic layer over the underlayer.
6. The magnetic thin film storage medium of claim 5 wherein the CrTiAl has from 5 to 20 at. % aluminum.
7. The magnetic thin film storage medium of claim 5 wherein the CrTiAl has approximately from 5 to 20 at. % aluminum with the remainder being approximately equal atomic percentages of chromium and titanium.
8. The magnetic thin film storage medium of claim 5 wherein the RuAl has a B2 crystallographic structure.
9. The magnetic thin film storage medium of claim 5 wherein the CrTiAl is approximately from 10 to 30 nm thick.
10. A method of fabricating a magnetic thin film storage medium comprising the steps of:
depositing a layer of CrTiAl on a substrate, the CrTiAl having an amorphous or nanocrystalline structure;
depositing a layer of RuAl over the layer of CrTiAl; and
depositing a plurality of layers over the layer of RuAl, including at least one magnetic layer.
11. The method of claim 10 wherein the CrTiAl has from 5 to 20 at. % aluminum.
12. The method of claim 10 wherein the CrTiAl has approximately from 5 to 20 at. % aluminum with the remainder being approximately equal atomic percentages of chromium and titanium.
13. The method of claim 10 wherein the RuAl has a B2 crystallographic structure.
14. The method of claim 10 wherein the CrTiAl is from approximately from 10 to 30 nm thick.
15. A disk drive comprising:
a magnetic transducer including a read and a write head;
a spindle; and
a magnetic thin film disk mounted on the spindle, the magnetic thin film disk including a layer of CrTiAl followed by a layer of RuAl and at least one magnetic layer, the CrTiAl having an amorphous or nanocrystalline structure.
16. The disk drive of claim 15 wherein the CrTiAl has from 5 to 20 at. % aluminum.
17. The disk drive of claim 15 wherein the CrTiAl has approximately from 5 to 20 at. % aluminum with the remainder being approximately equal atomic percentages of chromium and titanium.
18. The disk drive of claim 15 wherein the RuAl has a B2 crystallographic structure.
19. The disk drive of claim 15 wherein the CrTiAl is approximately from 10 to 30 nm thick.