Magnetic head for perpendicular recording with hard bias structure for write pole tip
View Patent ↗A magnetic head for writing information on a relatively-moving medium is disclosed, the head having a leading end, a trailing end and a medium-facing surface, the head comprising: a soft magnetic write pole that terminates in a pole tip that is disposed adjacent to the medium-facing surface; at least one coil section that is disposed adjacent to the write pole to induce a magnetic flux in the write pole; and a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip.
1. A magnetic head having a leading end, a trailing end and a medium-facing surface, the head comprising:
a soft magnetic write pole that terminates in a pole tip that is disposed adjacent to the medium-facing surface;
at least one coil section that is disposed adjacent to the write pole to induce a magnetic flux in the write pole; and
a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip.
2. The head of claim 1 , wherein the magnetic bias structure adjoins the write pole.
3. The head of claim 1 , wherein the magnetic bias structure is separated from the write pole by a submicron nonferromagnetic layer.
4. The head of claim 1 , wherein the magnetic bias structure includes a hard magnetic layer disposed adjacent to the pole tip.
5. The head of claim 4 , wherein the hard magnetic layers are separated from each other in a track-width direction.
6. The head of claim 1 , wherein the magnetic bias structure includes a plurality of hard magnetic layers disposed on opposite sides of the pole tip.
7. The head of claim 1 , wherein the pole tip has a trapezoidal shape.
8. A magnetic head having a leading end, a trailing end and a medium-facing surface, the head comprising:
a first ferromagnetic layer that terminates adjacent to the medium-facing surface in a first pole tip;
a second ferromagnetic layer that terminates adjacent to the medium-facing surface in a second pole tip, the second ferromagnetic layer being magnetically coupled to the first ferromagnetic layer, the second pole tip having an area that is at least two orders of magnitude greater than that of the first pole tip; and
a third ferromagnetic layer having a coercivity that is higher than that of the first and second ferromagnetic layers, the third ferromagnetic layer being disposed within one micron of the first pole tip to magnetically bias the first pole tip.
9. The head of claim 8 , wherein the third ferromagnetic layer adjoins the first ferromagnetic layer.
10. The head of claim 8 , wherein the third ferromagnetic layer is separated from the first ferromagnetic layer by a submicron nonferromagnetic layer.
11. The head of claim 8 , wherein the third ferromagnetic layer includes a hard magnetic layer disposed adjacent to the first pole tip.
12. The head of claim 8 , further comprising a fourth ferromagnetic layer that is disposed within one micron of the first pole tip and separated from the third ferromagnetic layer by the first pole tip.
13. The head of claim 12 , wherein the hard magnetic layers are separated from each other in a track-width direction.
14. The head of claim 12 , wherein the first pole tip has a trapezoidal shape.
15. A disk drive comprising:
a magnetic disk; and
a magnetic head including a soft magnetic write pole that terminates in a pole tip that is disposed adjacent to the medium-facing surface, at least one coil section that is disposed adjacent to the write pole to induce a magnetic flux in the write pole, and a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip.
16. The disk drive of claim 15 , wherein disk has a major surface and a media layer disposed adjacent to the major surface, the media layer having an easy axis of magnetization that is oriented substantially perpendicular to the major surface.
17. The disk drive of claim 15 , wherein the hard magnetic bias structure adjoins the write pole.
18. The disk drive of claim 15 , wherein the hard magnetic bias structure is separated from the write pole by a submicron nonferromagnetic layer.
19. The head of claim 15 , wherein the pole tip has a trapezoidal shape.
20. A disk drive comprising:
a magnetic disk; and
a magnetic head including a soft magnetic write pole that terminates in a pole tip that is disposed adjacent to the medium-facing surface, at least one coil section that is disposed adjacent to the write pole to induce a magnetic flux in the write pole, and a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip;
wherein the magnetic bias structure includes a plurality of hard magnetic layers disposed on opposite sides of the pole tip.
21. The disk drive of claim 20 , wherein the hard magnetic layers are separated from each other in a track-width direction.
22. A disk drive comprising:
a magnetic disk; and
a magnetic head including a soft magnetic write pole that terminates in a pole tip that is disposed adjacent to the medium-facing surface, at least one coil section that is disposed adjacent to the write pole to induce a magnetic flux in the write pole, and a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip;
wherein the magnetic bias structure includes a hard magnetic layer disposed adjacent to the pole tip.
23. A disk drive comprising:
a rigid disk having a major surface and a media layer disposed adjacent to the major surface, the media layer having an easy axis of magnetization that is oriented substantially perpendicular to the major surface; and
a head including a soft magnetic pole tip that is disposed adjacent to the disk to write information on the media layer, the head having a hard magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip.
24. The disk of claim 23 , wherein the hard magnetic bias structure adjoins the pole tip.
25. The disk of claim 23 , wherein the hard magnetic bias structure is separated from the pole tip by a submicron nonferromagnetic layer.
26. The disk of claim 23 , wherein the pole tip has a trapezoidal shape.
27. A disk drive comprising:
a rigid disk having a major surface and a media layer disposed adjacent to the major surface, the media layer having an easy axis of magnetization that is oriented substantially perpendicular to the major surface; and
a head including a soft magnetic pole tip that is disposed adjacent to the disk to write information on the media layer, the head having a magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip;
wherein the magnetic bias structure includes a plurality of hard magnetic layers disposed on opposite sides of the pole tip.
28. The disk of claim 27 , wherein the magnetic bias layers are separated from each other in a track-width direction.
29. A disk drive comprising:
a rigid disk having a major surface and a media layer disposed adjacent to the major surface, the media layer having an easy axis of magnetization that is oriented substantially perpendicular to the major surface; and
a head including a soft magnetic pole tip that is disposed adjacent to the disk to write information on the media layer, the head having a magnetic bias structure disposed within one micron of the pole tip to magnetically bias the pole tip;
wherein the magnetic bias structure includes a hard magnetic layer disposed adjacent to the pole tip.