Area density capacity improvement with negative anisotropic magnetic material trailing shield notch

Patent metadata

Field	Value
Publication number	US-11264052-B1
Application number	US-202117183190-A
Country	US
Kind code	B1
Filing date	Feb 23, 2021
Priority date	Feb 23, 2021
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

Embodiments of the present disclosure generally relate to a magnetic recording device comprising a magnetic recording head having a negative anisotropic magnetic (−Ku) material notch. The magnetic recording device comprises a main pole disposed at a media facing surface (MFS), a trailing shield disposed adjacent to the main pole, and a trailing gap disposed between the main pole and the trailing shield. The trailing shield comprises a hot seed layer disposed adjacent to the trailing gap, and a notch comprising a −Ku material in contact with the hot seed layer and the trailing gap. The notch is disposed adjacent to a first surface of the main pole at the MFS. The notch comprising the −Ku material results in an increased effective write magnetic field, an increased down-track field gradient due to reduced shunting from the main pole to the trailing shield, leading to an increased areal density capacity.

First claim

What is claimed is:

1. A magnetic recording head, comprising:
a main pole disposed at a media facing surface;
a trailing gap disposed adjacent to and in contact with a first surface of the main pole;
a notch disposed adjacent to and in contact with the trailing gap at the media facing surface, the notch comprising a negative anisotropic magnetic (−Ku) material, wherein the notch is substantially aligned with the first surface of the main pole at the media facing surface; and
a trailing shield coupled to the notch.

2. The magnetic recording head of claim 1 , wherein the notch has a width at the media facing surface of about 20 nm to about 100 nm and a thickness extending from the media facing surface into the magnetic recording head of about 2 nm to about 16 nm, and wherein the notch is spaced a distance of about 15 nm to about 25 nm from the first surface of the main pole.

3. The magnetic recording head of claim 1 , wherein the negative anisotropic material is a CoFe multilayer structure having a saturation magnetization of about 2.2 T and a uniaxial anisotropy between about −0.5 T and about −1 T.

4. The magnetic recording head of claim 1 , wherein the notch comprises a first layer of the negative anisotropic material and a second layer of CoFe.

5. The magnetic recording head of claim 4 , wherein the first layer of the negative anisotropic material is disposed in contact with the trailing gap and the second layer of CoFe is disposed adjacent to the first surface of the main pole.

6. The magnetic recording head of claim 4 , wherein the first layer of the negative anisotropic material is disposed in contact with the trailing shield and the second layer of CoFe is disposed adjacent to the first surface of the main pole.

7. A magnetic recording device, comprising:
a magnetic recording head, comprising:
a main pole disposed at a media facing surface;
a trailing gap disposed adjacent to and in contact with a first surface of the main pole;
a notch disposed adjacent to and in contact with the trailing gap at the media facing surface, the notch comprising a negative anisotropic magnetic (−Ku) material, wherein the notch is substantially aligned with the first surface of the main pole at the media facing surface; and
a trailing shield coupled to the notch.

8. A magnetic recording head, comprising:
a trailing shield disposed at a media facing surface, the trailing shield comprising a hot seed layer;
a notch coupled to the hot seed layer at the media facing surface, the notch comprising a negative anisotropic magnetic (−Ku) material having a saturation magnetization between about 2.0 T to about 2.5 T, and a uniaxial anisotropy between about −0.5 T to about −1.5 T;
a trailing gap disposed adjacent to the notch, the trailing gap surround a first surface, a second surface, and a third surface of the notch; and
a main pole disposed adjacent to the trailing gap.

9. The magnetic recording head of claim 8 , wherein the notch has a first width at the media facing surface less than a second width of the hot seed layer at the media facing surface, the first width of the notch being about 20 nm to about 100 nm.

10. The magnetic recording head of claim 8 , wherein the negative anisotropic material is a CoFe multilayer structure comprising alternating layers of Co layers having a thickness between about 0.2 nm about 0.6 nm and Fe layers having a thickness between about 0.4 nm to about 0.8 nm.

11. The magnetic recording head of claim 8 , wherein the notch is a multi-layer structure comprising a first layer of the negative anisotropic material and a second layer of CoFe.

12. The magnetic recording head of claim 8 , wherein the notch has a first thickness extending from the media facing surface into the magnetic recording head of about 2 nm to about 16 nm, and wherein the hot seed layer has a second thickness extending from the media facing surface into the magnetic recording head substantially equal to the first thickness of the notch.

13. A magnetic recording device, comprising:
a magnetic recording head, comprising:
a trailing shield disposed at a media facing surface, the trailing shield comprising a hot seed layer;
a notch coupled to the hot seed layer at the media facing surface, the notch comprising a negative anisotropic magnetic (−Ku) material having a saturation magnetization between about 2.0 T to about 2.5 T, and a uniaxial anisotropy between about −0.5 T to about −1.5 T;
a trailing gap disposed adjacent to the notch, the trailing gap surround a first surface, a second surface, and a third surface of the notch; and
a main pole disposed adjacent to the trailing gap.

14. A magnetic recording head, comprising:
a leading shield;
a main pole having a first surface disposed at a media facing surface, the main pole comprising a leading side taper recessed a first distance from the media facing surface and a trailing side taper recessed a second distance from the media facing surface;
a trailing gap disposed adjacent to the main pole and the trailing side taper;
a notch disposed adjacent to the trailing gap, the notch comprising a negative anisotropic magnetic (−Ku) material, wherein the notch has a first surface disposed at the media facing surface; and
a trailing shield comprising a hot seed layer, the hot seed layer being coupled to the notch.

15. The magnetic recording head of claim 14 , wherein the notch has a first thickness extending from the media facing surface into the magnetic recording head, the first thickness of the notch being less than the second distance the trailing side taper is recessed from the media facing surface, and wherein the hot seed layer has a second thickness extending from the media facing surface into the magnetic recording head, the first thickness of the notch being substantially equal to the second thickness of the hot seed layer.

16. The magnetic recording head of claim 14 , wherein the notch has a first width at the media facing surface of about 20 nm to about 100 nm, and wherein the notch is spaced a distance of about 15 nm to about 25 nm from the first surface of the main pole.

17. The magnetic recording head of claim 16 , wherein the notch is substantially aligned with the first surface of the main pole and the media facing surface, and wherein the first surface of the main pole has a second width substantially equal to the first width of the notch.

18. The magnetic recording head of claim 14 , wherein the notch comprises a first layer of the negative anisotropic material coupled to the hot seed layer and a second layer of CoFe disposed adjacent to the first surface of the main pole, the negative anisotropic material having a saturation magnetization between about 2.0 T to about 2.5 T, and a uniaxial anisotropy between about −0.5 T to about −1.5 T.

19. The magnetic recording head of claim 14 , wherein the notch comprises a first layer of the negative anisotropic material disposed adjacent to the first surface of the main pole and a second layer of CoFe coupled to the hot seed layer, the negative anisotropic material having a saturation magnetization between about 2.0 T to about 2.5 T, and a uniaxial anisotropy between about −0.5 T to about −1.5 T.

20. A magnetic recording device, comprising:
a magnetic recording head, comprising:
a leading shield;
a main pole having a first surface disposed at a media facing surface, the main pole comprising a leading side taper recessed a first distance from the media facing surface and a trailing side taper recessed a second distance from

Assignees

• Western Digital Tech Inc

Inventors

• Song Suping
• Guan Lijie
• Lam Terence
• Shi Changqing

Classifications

• H01F10/16

  containing cobalt ({H01F10/126} , H01F10/13 take precedence) · CPC title

• G11B5/3156

  providing interaction by induced or exchange coupling · CPC title

• G11B5/315 Primary

  Shield layers on both sides of the main pole, e.g. in perpendicular magnetic heads · CPC title

• G11B5/3912

  Arrangements in which the active read-out elements are transducing in association with active magnetic shields, e.g. magnetically coupled shields (G11B5/3916 takes precedence) · CPC title

• H01F1/047

  Alloys characterised by their composition · CPC title