Apparatuses and methods for providing thin shields in a multiple sensor array

Patent metadata

Field	Value
Publication number	US-9786301-B1
Application number	US-201414557941-A
Country	US
Kind code	B1
Filing date	Dec 2, 2014
Priority date	Dec 2, 2014
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

Apparatuses and methods for providing thin shields in a multiple sensor array are provided. One such apparatus is a magnetic read transducer including a first read sensor, a second read sensor, and a shield assembly positioned between the first read sensor and the second read sensor at an air bearing surface (ABS) of the magnetic read transducer, the shield assembly including a first shield layer assembly having a first footprint with a first area, and a second shield layer assembly having a second footprint with a second area, where the second area is greater than the first area.

First claim

What is claimed is:

1. A magnetic read transducer comprising:
a first read sensor;
a second read sensor; and
a shield assembly positioned between the first read sensor and the second read sensor at an air bearing surface (ABS) of the magnetic read transducer in a down track direction, the shield assembly comprising:
a first shield layer assembly having a first footprint with a first area; and
a second shield layer assembly having a second footprint with a second area,
wherein the second area is greater than the first area, and
wherein a majority of the first area and a majority of the second area are positioned on opposite sides of the first read sensor in a cross track direction.

2. The magnetic read transducer of claim 1 :
wherein first shield layer assembly comprises a first preselected number of layers comprising a plurality of laminated soft ferromagnetic layers; and
wherein second shield layer assembly comprises a second preselected number of layers comprising a plurality of laminated soft ferromagnetic layers.

3. The magnetic read transducer of claim 1 :
wherein first shield layer assembly comprises a first preselected number of layers;
wherein second shield layer assembly comprises a second preselected number of layers; and
wherein the first preselected number of layers does not equal the second preselected number of layers.

4. The magnetic read transducer of claim 3 , wherein the first preselected number of layers is greater than the second preselected number of layers.

5. The magnetic read transducer of claim 4 , further comprising:
an insulating layer between the first shield layer assembly and the second shield layer assembly,
wherein the first shield layer assembly comprises:
a first soft ferromagnetic layer;
an anti-ferromagnetic exchange coupling layer assembly on the first soft ferromagnetic layer;
a second soft ferromagnetic layer on the anti-ferromagnetic exchange coupling layer assembly;
an anti-ferromagnetic pinning layer on the second soft ferromagnetic layer; and
a capping layer on the anti-ferromagnetic pinning layer; and

wherein the second shield layer assembly comprises:
a third soft ferromagnetic layer;
a second anti-ferromagnetic exchange coupling layer on the third soft ferromagnetic layer; and
a fourth soft ferromagnetic layer on the second anti-ferromagnetic exchange coupling layer.

6. The magnetic read transducer of claim 5 :
wherein the anti-ferromagnetic exchange coupling layer assembly of the first shield layer assembly comprises:
a first anti-ferromagnetic exchange coupling enhancer layer;
a first anti-ferromagnetic exchange coupling layer on the first anti-ferromagnetic exchange coupling enhancer layer; and
a second anti-ferromagnetic exchange coupling enhancer layer on the first anti-ferromagnetic exchange coupling layer,

wherein the first shield layer assembly further comprises a third anti-ferromagnetic exchange coupling enhancer layer positioned between the second soft ferromagnetic layer and the anti-ferromagnetic pinning layer.

7. The magnetic read transducer of claim 1 :
wherein the first shield layer assembly has a thickness of less than 40 nanometers; and
wherein the second shield layer assembly has a thickness of less than 40 nanometers.

8. The magnetic read transducer of claim 1 :
wherein the first read sensor is spaced apart from the second read sensor along a direction substantially parallel to the shield assembly to enable two dimensional magnetic recording.

9. The magnetic read transducer of claim 8 , further comprising:
a third read sensor;
a second shield assembly positioned between the second read sensor and the third read sensor, the second shield assembly comprising:
a third shield layer assembly having a third footprint with a third area; and
a fourth shield layer assembly having a fourth footprint with a fourth area,
wherein the fourth area is greater than the third area.

10. The magnetic read transducer of claim 1 :
wherein the first read sensor comprises a first edge at the ABS and a second edge at a second surface substantially parallel to the ABS;
wherein the first shield layer assembly comprises an edge substantially parallel to and closest to the second edge of the first read sensor;
wherein the second shield layer assembly comprises an edge substantially parallel to and closest to the second edge of the first read sensor; and
wherein the edge of the first shield layer assembly is positioned between the edge of the second shield layer assembly and the second edge of the first read sensor.

11. The magnetic read transducer of claim 1 , further comprising:
a first main shield layer substantially parallel to the shield assembly;
a first soft bias layer on the first main shield layer;
a second soft bias layer substantially parallel to the shield assembly; and
a second main shield layer on the second soft bias layer,
wherein the first read sensor is positioned between a right side portion of the first soft bias layer and a left side portion of the first soft bias layer at the ABS; and
wherein the second read sensor is positioned between a right side portion of the second soft bias layer and a left side portion of the second soft bias layer at the ABS.

12. The magnetic read transducer of claim 1 , wherein the first footprint is not symmetric to the second footprint.

13. A magnetic read transducer comprising:
a first read sensor;
a second read sensor;
a shield assembly positioned between the first read sensor and the second read sensor at an air bearing surface (ABS) of the magnetic read transducer, the shield assembly comprising:
a first shield layer assembly having a first footprint with a first area; and
a second shield layer assembly having a second footprint with a second area,
wherein the second area is greater than the first area;

a soft bias layer substantially parallel to the shield assembly; and
a hard bias layer substantially parallel to the shield assembly,
wherein the first read sensor is positioned between a right side portion of the soft bias layer and a left side portion of the soft bias layer at the ABS; and
wherein the soft bias layer is positioned between a right side portion of the hard bias layer and a left side portion of the hard bias layer at the ABS.

14. A method of fabricating a magnetic read transducer, the method comprising:
providing a first read sensor at an air bearing surface (ABS) of the magnetic read transducer;
providing a shield assembly on the first read sensor, wherein the providing the shield assembly on the first read sensor comprises:
providing a first shield layer assembly on the first read sensor, the first shield layer assembly having a first footprint with a first area; and
providing a second shield layer assembly on the first shield layer assembly, the second shield layer assembly having a second footprint with a second area, wherein the second area is greater than the first area; and

providing a second read sensor on the shield assembly,
wherein a majority of the first area and a majority of the second area are positioned on opposite sides of the first read sensor in a cross track direction.

15. The method of claim 14 :
wherein first shield layer assembly comprises a first preselected number of layers comprising a plurality of laminated soft ferromagnetic layers; and
wherein second shield layer assembly comprises a second preselected number of layers comprising a plurality of laminated soft ferromagnetic layers.

16. The method of claim 14 :
wherein first shield layer assembly comp

Assignees

• Western Digital (Fremont) Llc

Inventors

• Li Shaoping
• Bertero Gerardo A
• Rudy Steven C
• He Shihai
• Mao Ming
• Xi Haiwen
• Ganesan Srikanth
• Leng Qunwen
• Yi Ge
• Xiao Rongfu
• Liu Feng
• Wang Lei

Classifications

• G11B5/6005

  Specially adapted for spacing from a rotating disc using a fluid cushion · CPC title

• G11B5/3951

  the active elements being arranged on several parallel planes · CPC title

• G11B5/11 Primary

  Shielding of head against electric or magnetic fields · 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

• G11B5/112

  Manufacture of shielding device · CPC title