Magnetic write head for providing spin-torque-assisted write field enhancement

Patent metadata

Field	Value
Publication number	US-2020234729-A1
Application number	US-202016748881-A
Country	US
Kind code	A1
Filing date	Jan 22, 2020
Priority date	Apr 28, 2016
Publication date	Jul 23, 2020
Grant date	—

Abstract

Disclosed herein are magnetic write heads for providing spin-torque-assisted write field enhancement, and hard disk drives comprising such magnetic write heads. Within the write gap, each magnetic write head comprises a main pole, a trailing shield, a spacer disposed between the main pole and the trailing shield, a non-magnetic layer disposed between the main pole and the trailing shield, and a magnetic DC-field-generation (DFG) layer adjacent to the spacer and disposed between the spacer and the non-magnetic layer. In some embodiments, the DFG layer is the only magnetic layer within the write gap that is not adjacent to the main pole or the trailing shield.

First claim

What is claimed is:

1 - 22 . (canceled)

23 . A perpendicular magnetic recording writer, comprising:
a main pole disposed adjacent to a first side of a write gap at an air-bearing surface (ABS); a trailing shield adjacent to a second side of the write gap at the ABS; and a spin-torque-assisting element disposed in the write gap and extending to the ABS, the spin-torque-assisting element comprising:
a non-magnetic layer in contact with the main pole;
a DC-field generation (DFG) layer, wherein a first side of the DFG layer is in contact with the non-magnetic layer; and
a spacer layer in contact with a second side of the DFG layer,
wherein a magnetization of the DFG layer is configured to be aligned substantially parallel to a gap field in response to the gap field being generated by the main pole during a write process, and wherein the magnetization of the DFG layer is configured to flip to a direction substantially opposite to the gap field in response to application of a bias current exceeding a specified magnitude in a direction from the trailing shield toward the main pole.

24 . The perpendicular magnetic recording writer recited in claim 23 , wherein a downtrack dimension thickness of the spin-torque-assisting element is approximately equal to a thickness of the write gap.

25 . The perpendicular magnetic recording writer recited in claim 23 , wherein the DFG layer is the only magnetic layer within the write gap that is not adjacent to the main pole or the trailing shield.

26 . The perpendicular magnetic recording writer recited in claim 23 , wherein an effective write gap thickness is between approximately 15 nm and approximately 25 nm.

27 . The perpendicular magnetic recording writer recited in claim 23 , wherein a thickness of the spin-torque assisting element at the ABS is between approximately 16.5 nm and approximately 27.5 nm.

28 . The perpendicular magnetic recording writer recited in claim 23 , wherein the non-magnetic layer comprises nickel, chromium, aluminum, ruthenium, tantalum, copper, a nickel-aluminum alloy, or a nickel-chromium alloy.

29 . The perpendicular magnetic recording writer recited in claim 23 , wherein the DFG layer comprises a first layer and a second layer.

30 . The perpendicular magnetic recording writer recited in claim 29 , wherein:
the first layer comprises at least one of cobalt, iron, or a cobalt-iron alloy, and the second layer comprises a cobalt alloy denoted as CoXM, wherein X is manganese or iron, and M is germanium, aluminum, silicon, or gallium.

31 . The perpendicular magnetic recording writer recited in claim 23 , wherein the spacer layer comprises copper, silver, gold, or an alloy of copper, silver, or gold.

32 . The perpendicular magnetic recording writer recited in claim 23 , wherein the specified magnitude is greater than a critical value that causes a DC component of the magnetization of the DFG layer to substantially oppose the gap field.

33 . The perpendicular magnetic recording writer recited in claim 32 , wherein the critical value is less than or equal to approximately 5 mA.

34 . The perpendicular magnetic recording writer recited in claim 32 , wherein the critical value is dependent on at least one characteristic of the DFG layer.

35 . The perpendicular magnetic recording writer recited in claim 34 , wherein the at least one characteristic comprises a thickness of the DFG layer.

36 . The perpendicular magnetic recording writer recited in claim 35 , wherein the thickness of the DFG layer is approximately 3 nm, and the critical value is less than or equal to approximately 5 mA.

37 . The perpendicular magnetic recording write recited in claim 23 , further comprising a magnetic notch between the trailing shield and the main pole, wherein the trailing shield and the magnetic notch or the main pole and the magnetic notch are made of identical materials.

38 . The perpendicular magnetic recording writer recited in claim 23 , further comprising a magnetic notch between the trailing shield and the spacer.

39 . The perpendicular magnetic recording writer recited in claim 38 , wherein a thickness of the magnetic notch is between about 1 nm and about 10 nm.

40 . A data storage device comprising the perpendicular magnetic recording writer recited in claim 23 .

41 . A perpendicular magnetic recording writer, comprising:
a main pole disposed adjacent to a first side of a write gap at an air-bearing surface (ABS); a trailing shield adjacent to a second side of the write gap at the ABS; and a spin-torque-assisting element disposed in the write gap and extending to the ABS, the spin-torque-assisting element comprising:
a non-magnetic layer in contact with the trailing shield;
a DC-field generation (DFG) layer, wherein a first side of the DFG layer is in contact with the non-magnetic layer; and
a spacer layer in contact with a second side of the DFG layer,
wherein a magnetization of the DFG layer is configured to be aligned substantially parallel to a gap field in response to the gap field being generated by the main pole during a write process, and wherein the magnetization of the DFG layer is configured to flip to a direction substantially opposite to the gap field in response to application of a bias current exceeding a specified magnitude in a direction from the main pole toward the trailing shield.

42 . The perpendicular magnetic recording writer recited in claim 41 , wherein a downtrack dimension thickness of the spin-torque-assisting element is approximately equal to a thickness of the write gap.

43 . The perpendicular magnetic recording writer recited in claim 41 , wherein the DFG layer is the only magnetic layer within the write gap that is not adjacent to the main pole or the trailing shield.

44 . The perpendicular magnetic recording writer recited in claim 41 , wherein an effective write gap thickness is between approximately 15 nm and approximately 25 nm.

45 . The perpendicular magnetic recording writer recited in claim 41 , wherein a thickness of the spin-torque assisting element at the ABS is between approximately 16.5 nm and approximately 27.5 nm.

46 . The perpendicular magnetic recording writer recited in claim 41 , wherein the non-magnetic layer comprises nickel, chromium, aluminum, ruthenium, tantalum, copper, a nickel-aluminum alloy, or a nickel-chromium alloy.

47 . The perpendicular magnetic recording writer recited in claim 41 , wherein the DFG layer comprises a first layer and a second layer.

48 . The perpendicular magnetic recording writer recited in claim 47 , wherein:
the first layer comprises at least one of cobalt, iron, or a cobalt-iron alloy, and the second layer comprises a cobalt alloy denoted as CoXM, wherein X is manganese or iron, and M is germanium, aluminum, silicon, or gallium.

49 . The perpendicular magnetic recording writer recited in claim 41 , wherein the spacer layer comprises copper, silver, gold, or an alloy of copper, silver, or gold.

50 . The perpendicular magnetic recording writer recited in claim 41 , wherein the specified magnitude is greater than a critical value that causes a DC component of the magnetization of the DFG layer to substantially oppose the gap field.

51 . The perpendicular magnetic recording writer recited in claim 50 , wherein the critica

Assignees

• Western Digital Tech Inc

Inventors

• Olson James Terrence
• Hoshiya Hiroyuki
• Goncharov Alexander
• Shiimoto Masato
• Sugiyama Mikito

Classifications

• G11B5/314 Primary

  where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence) · CPC title

• G11B2005/0024

  Microwave assisted recording · CPC title

• G11B5/3929 Primary

  Disposition of magnetic thin films not used for directly coupling magnetic flux from the track to the MR film or for shielding · CPC title

• G11B5/012

  Recording on, or reproducing or erasing from, magnetic disks (G11B17/00, G11B19/00 take precedence) · 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