Magnetic recording write apparatus having a pole having an aspect ratio greater than one and an auxiliary pole
View Patent ↗A magnetic write apparatus has a media-facing surface (MFS) and includes an auxiliary pole, coil(s) and a main pole having a pole tip and a yoke. The pole tip occupies part of the MFS. The yoke has a yoke length measured from the MFS in a yoke direction perpendicular to the MFS. The yoke length is less than four microns. The main pole has a total length in the yoke direction and a width in a cross-track direction. The main pole is continuous along the total length. The aspect ratio of the main pole is the total length divided by the width and exceeds one. The main pole includes surface(s) having a nonzero acute flare angle from the MFS. The auxiliary pole is adjacent to the main pole and recessed from the MFS by not more than 1.05 micron. The coil(s) energizes the main pole and have not more than two turns.
1. A magnetic write apparatus having a media-facing surface (MFS) comprising:
a main pole including a pole tip and a yoke, the pole tip occupying a portion of the MFS and being between the yoke and the MFS, the yoke having a yoke length in a yoke direction perpendicular to the MFS, the yoke length being measured from the MFS and being less than four microns, the main pole having a total length in the yoke direction and a width in a cross-track direction parallel to the MFS, the main pole being continuous along the total length, the total length being measured from the MFS to a pole back and being greater than the yoke length, an aspect ratio being the total length divided by the width, the aspect ratio exceeding one, the main pole including at least one side surface having a flare angle from the MFS, the flare angle being nonzero and acute;
an auxiliary pole adjacent to the main pole and having a front surface recessed from the MFS by not more than 1.05 micron; and
at least one coil for energizing the main pole, the at least one coil having not more than two turns.
2. The magnetic write apparatus of claim 1 wherein the aspect ratio is at least 1.2 and not more than 2.
3. The magnetic write apparatus of claim 1 wherein the flare angle is at least thirty degrees and not more than seventy degrees.
4. The magnetic write apparatus of claim 3 wherein the flare angle is at a flare point at least 0.1 micron and not more than 0.45 micron from the MFS.
5. The magnetic write apparatus of claim 1 wherein the auxiliary pole is recessed by at least 0.1 micron and not more than 0.45 micron from the MFS.
6. The magnetic write apparatus of claim 5 wherein the auxiliary pole has a thickness in a down track direction perpendicular to the cross-track direction of at least 0.2 micron and not more than 0.5 micron.
7. The magnetic write apparatus of claim 5 wherein the auxiliary pole has a plurality of sides at at least one angle from a down track direction perpendicular to the cross-track direction, the at least one angle being at least fifteen degrees and not more than fifty degrees.
8. The magnetic write apparatus of claim 5 wherein the auxiliary pole includes at least one magnetic material having a saturation magnetization of at least 2.4 T.
9. The magnetic write apparatus of claim 5 wherein the auxiliary pole has an auxiliary pole width in the cross-track direction, the auxiliary pole width being not wider than the width and not smaller than 0.3 micrometers less than the width of the main pole.
10. The magnetic write apparatus of claim 1 wherein the main pole has at least one back corner having a radius of curvature of at least two microns and not more than four microns.
11. The magnetic write apparatus of claim 1 further comprising:
a trailing shield; and
a write gap, a portion of the write gap residing between the trailing shield and the pole tip.
12. The magnetic write apparatus of claim 1 wherein the total length is not more than ten microns.
13. A data storage device comprising:
a media; and
a magnetic write apparatus having a media-facing surface (MFS), the magnetic write apparatus including a main pole, an auxiliary pole and at least one coil for energizing the main pole, the at least one coil having not more than two turns, the main pole including a pole tip and a yoke, the pole tip occupying a portion of the MFS and being between the yoke and the MFS, the yoke having a yoke length in a yoke direction perpendicular to the MFS, the yoke length being measured from the MFS and less than four microns, the main pole having a total length in the yoke direction and a width in a cross-track direction parallel to the MFS, the total length being measured from the MFS to a pole back and being greater than the yoke length, the main pole being continuous along the total length, an aspect ratio being the total length divided by the width, the aspect ratio exceeding one, the main pole including at least one side surface having a flare angle from the MFS, the flare angle being nonzero and acute, the auxiliary pole adjacent to the main pole and having a front surface recessed from the MFS by not more than 1.05 micron.
14. The data storage device of claim 13 wherein the aspect ratio is at least 1.2 and not more than 2, the flare angle is at least thirty degrees and not more than seventy degrees and the flare angle is at a flare point at least 0.1 micron and not more than 0.45 micron from the MFS.
15. The data storage device of claim 13 wherein the auxiliary pole is recessed by at least 0.1 micron and not more than 0.45 micron from the MFS, the auxiliary pole has a thickness in a down track direction perpendicular to the cross-track direction of at least 0.2 micron and not more than 0.5 micron, the auxiliary pole includes at least one magnetic material having a saturation magnetization of at least 2.4 T and the auxiliary pole has a plurality of sides at at least one angle from a down track direction perpendicular to the cross-track direction, the at least one angle being at least fifteen degrees and not more than fifty degrees, the auxiliary pole having an auxiliary pole width in the cross-track direction, the auxiliary pole width being not wider than the width and not smaller than 0.3 micrometers less than the width of the main pole.
16. The data storage device of claim 13 wherein the main pole has at least one back corner having a radius of curvature of at least two microns and not more than four microns and wherein the total length is not more than ten microns.
17. A method for providing a magnetic write apparatus having a media-facing surface (MFS) comprising:
providing an auxiliary pole having a front surface recessed from the MFS by not more than 1.05 micron;
providing a main pole adjacent to the auxiliary pole, the main pole including a pole tip and a yoke, the pole tip occupying a portion of the MFS and being between the yoke and the MFS, the yoke having a yoke length in a yoke direction perpendicular to the MFS, the yoke length being measured from the MFS and less than four microns, the main pole having a total length in the yoke direction and a width in a cross-track direction parallel to the MFS, the total length being measured from the MFS to a pole back and being greater than the yoke length, the main pole being continuous along the total length, an aspect ratio being the total length divided by the width, the aspect ratio exceeding one, the main pole including at least one side surface having a flare angle from the MFS, the flare angle being nonzero and acute; and
providing at least one coil for energizing the main pole, the at least one coil having not more than two turns.
18. The method of claim 17 wherein the step of providing the auxiliary pole further includes:
forming an auxiliary pole trench in a first nonmagnetic layer, the auxiliary pole trench having a shape and location corresponding to the auxiliary pole;
depositing an etch stop layer after the step of forming the auxiliary pole trench;
providing a sacrificial layer, the sacrificial layer filling the auxiliary pole trench; and
wherein the step of providing the main pole further includes depositing a second nonmagnetic layer;
forming a main pole trench in at least the second nonmagnetic layer, a portion of the sacrificial layer being exposed by the main pole trench;
removing a remaining portion of the sacrificial layer using a wet etch; and
providing a high saturation magnetization magnetic layer, the high saturation magnetization magnetic layer filling the auxiliary pole trench and at least a portion of the main pole trench.
19. The method of claim 18 wherein the sacrificial layer is selected from NiFe, a CoNiFe, aluminum oxide and Cu.
20. The method of claim 17 wherein the aspect ratio is at least 1.2 and not more than 2, the flare angle is at least thirty degrees and not more than seventy degrees and the flare angle is at a flare point at least 0.1 micron and not more than 0.45 micron from the MFS.
21. The method of claim 17 wherein the auxiliary pole is recessed by at least 0.1 micron and not more than 0.45 micron from the MFS, the auxiliary pole has a thickness in a down track direction perpendicular to the cross-track direction of at least 0.2 micron and not more than 0.5 micron, the auxiliary pole includes at least one magnetic material having a saturation magnetization of at least 2.4 T and the auxiliary pole has a plurality of sides at at least one angle from a down track direction perpendicular to the cross-track direction, the at least one angle being at least fifteen degrees and not more than fifty degrees, the auxiliary pole having an auxiliary pole width in the cross-track direction, the auxiliary pole width being not wider than the width of the main pole and not smaller than 0.3 micrometers less than the width of the main pole.
22. The method of claim 17 wherein the main pole has at least one back corner having a radius of curvature of at least two microns and not more than four microns and wherein the total length is not more than ten microns.