Perpendicular magnetic write head having a controlled magnetization state shield
View Patent ↗Embodiments disclosed herein generally relate to a perpendicular magnetic recording head for recording magnetic information and a magnetic recording device employing the magnetic head. The magnetic recording head comprises at least one thin shield region having a high coercive force and a magnetization direction oriented towards the right when viewed from the MFS with the leading side on bottom and the trailing side on top, and at least one thick shield region having a low coercive force. The thin shield region surrounds a main pole, and the thick shield region partially surrounds the thin shield region. The magnetic recording head is able to reduce FTI by controlling the magnetization direction of the shield layers.
1. A perpendicular magnetic recording head having a leading side and a trailing side, comprising:
a main pole;
a media facing surface;
a first shield region enclosing all sides of the main pole, the first shield region having a magnetization direction oriented towards the right when the leading side is disposed on the bottom of the media facing surface and the trailing side is disposed on the top of the media facing surface; and
a second shield region coupled to the first shield region, wherein the second shield region is thicker than the first shield region, wherein thickness is measured from the media facing surface into the head.
2. The perpendicular magnetic recording head of claim 1 , wherein a coercive force of the first shield region is greater than a coercive force of the second shield region.
3. The perpendicular magnetic recording head of claim 1 , wherein a magnetization direction of the first shield region is anti-parallel to a magnetization direction of the second shield region.
4. The perpendicular magnetic recording head of claim 1 , wherein a magnetization direction of the first shield region is parallel to a magnetization direction of the second shield region.
5. The perpendicular magnetic recording head of claim 1 , wherein the first shield region has an essentially equal width and height.
6. The perpendicular magnetic recording head of claim 5 , wherein the second shield region is thicker than the first shield region by about 100 nm, wherein thickness is measured from a media facing surface into the head.
7. The perpendicular magnetic recording head of claim 6 , wherein the first shield region has a thickness of about 200 nm and the second shield region has a thickness of about 300 nm or greater.
8. A perpendicular magnetic recording head having a leading side and a trailing side, comprising:
a main pole;
a media facing surface;
a first shield region enclosing all sides of the main pole, the first shield region having a magnetization direction oriented towards the right when the leading side is disposed on the bottom of the media facing surface and the trailing side is disposed on the top of the media facing surface, wherein the first shield region has an essentially equal width and height;
a second shield region coupled to the first shield region; and
a third shield region coupled to the first shield region.
9. The perpendicular magnetic recording head of claim 8 , wherein a fourth shield region is coupled the third shield region, the fourth shield region being thinner than the third shield region, and wherein the fourth shield region is disposed on the leading side.
10. The perpendicular magnetic recording head of claim 9 , wherein the first shield region and the fourth shield region have a parallel magnetization direction and the second shield region and the third shield region have a parallel magnetization direction.
11. The perpendicular magnetic recording head of claim 10 , wherein the first shield region and the second shield region have an anti-parallel magnetization direction and the third shield region and the fourth shield region have an anti-parallel magnetization direction.
12. The perpendicular magnetic recording head of claim 1 , wherein the first shield region has a coercive force greater than the coercive force of the second shield region by at least 100 Oe.
13. A magnetic recording device, comprising:
one or more magnetic disks;
an actuator;
an actuator arm coupled to the actuator; and
a perpendicular magnetic recording head having a leading side and a trailing side coupled to the actuator arm, the perpendicular magnetic recording head comprising:
a main pole;
a media facing surface;
a first shield region enclosing all sides of the main pole, the first shield region having a magnetization direction oriented towards the right when the leading side is disposed on the bottom of the media facing surface and the trailing side is disposed on the top of the media facing surface; and
a second shield region coupled to the first shield region and disposed on the leading side, wherein the second shield region is thicker than the first shield region, wherein thickness is measured from the media facing surface into the head.
14. The magnetic recording device of claim 13 , wherein a coercive force of the first shield region is greater than a coercive force of the second shield region.
15. The magnetic recording device of claim 14 , wherein a magnetization direction of the first shield region is parallel to a magnetization direction of the second shield region.
16. The magnetic recording device of claim 14 , wherein the second shield region is thicker than the first shield region by about 100 nm.
17. The magnetic recording device of claim 14 , wherein a magnetization direction of the first shield region is anti-parallel to a magnetization direction of the second shield region.
18. A magnetic recording device, comprising:
one or more magnetic disks;
an actuator;
an actuator arm coupled to the actuator; and
a perpendicular magnetic recording head having a leading side and a trailing side coupled to the actuator arm, the perpendicular magnetic recording head comprising:
a main pole;
a media facing surface;
a first shield region enclosing all sides of the main pole, the first shield region having a magnetization direction oriented towards the right when the leading side is disposed on the bottom of the media facing surface and the trailing side is disposed on the top of the media facing surface; and
a second shield region coupled to the first shield region and disposed on the leading side, wherein a coercive force of the first shield is greater than a coercive force of the second shield, and wherein the magnetization direction of the first shield region is anti-parallel to a magnetization direction of the second shield region; and.
a third shield region is coupled to the first shield region and a fourth shield region is coupled to the third shield region, the fourth shield region being thinner than the third shield region, and wherein the fourth shield region is disposed on the leading side.
19. The magnetic recording device of claim 14 , wherein the first shield region is disposed on the leading side of the perpendicular magnetic recording head.
20. The magnetic recording device of claim 14 , wherein the second shield region is disposed on the trailing side of the perpendicular magnetic recording head.