Recessed write gap material for enhanced bias current injection and maximizing aerial density capacity in perpendicular magnetic recording

Patent metadata

Field	Value
Publication number	US-12469518-B1
Application number	US-202418818344-A
Country	US
Kind code	B1
Filing date	Aug 28, 2024
Priority date	Aug 28, 2024
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

The present embodiments relate to a magnetic write head structure that improves the maximum allowable bias current to maximize the current-assisted areal density capacity (ADC) gain in hard-disk-drive storage device. The write head can include a magnetic main pole (MP) and a trailing shield (TS) made of magnetic material that collects back the magnetic flux and a write gap (WG) between the MP and the TS that is comprised of a non-magnetic electrical conductor. The WG can include a height that is greater than an eTHd height of the HS that can increase an electrical contact area between the HS and MP for a bias current flow. The WG can further include a first part extending an air-bearing surface (ABS) plane of the write head to a top of the eTHd height and a second part extending from the top of the eTHd height.

First claim

What is claimed is:

1 . A write head for a disk drive, the write head comprising:
a main pole (MP) configured to provide a magnetic flux to a recording medium; a trailing shield (TS) comprising a hot seed (HS) and write shield (WS) to collect a portion of the flux from the MP; a write gap (WG) disposed between the MP and TS, wherein the WG comprises a non-magnetic electrically conductive material; a side shield (SS), a leading shield (LS), and a write shield (WS) each comprising a magnetic material that prevents magnetic flux from reaching the medium bits away from the MP, wherein a length of the WG is disposed along a length of the SS and the LS and is about equal to a length of the HS; a side gap (SG) between the MP and the SS on multiple sides of the MP, wherein the SG comprises a non-magnetic material that is a conductor or an insulator; and a leading gap (LG) between the MP and the LS, the LG comprising a same material as the SG.

2 . The write head of claim 1 , wherein a thickness of the WG is about equal to a thickness of the HS.

3 . The write head of claim 1 , wherein a height of the WG is greater than an extended throat (eTHd) height of the HS, which is configured to increase an electrical contact area between the HS and MP for a bias current flow.

4 . The write head of claim 3 , wherein the WG comprises:
a first part extending an air-bearing surface (ABS) plane of the write head to a top of the eTHd height; and a second part extending from the top of the eTHd height.

5 . The write head of claim 4 , wherein a thickness of the first part of the WG is uniform across the ABS plane to the eTHd height, and wherein a thickness of the second part of the WG increases with the height of the WG and is based on a shape of the HS.

6 . The write head of claim 1 , wherein the LG and the SG comprise an electrical insulator material comprising aluminum oxide (Al 2 O 3 ).

7 . The write head of claim 1 , wherein the LG and the SG comprise an electrical conductor comprising Ruthenium (Ru) or a Nickel-Chromium (NiCr)/Ruthenium (Ru) multilayer.

8 . A device comprising:
a main pole (MP); a trailing shield (TS) comprising a hot seed (HS) and write shield (WS); a write gap (WG) disposed between the MP and TS, wherein the WG comprises a first part extending from an air-bearing surface ABS plane to a top of a eTHd height of the HS, and a second part from the top of the eTHd height; a side shield (SS), a leading shield (LS), and a write shield (WS), wherein a length of the WG is disposed along a length of the SS and the LS is about equal to a length of the HS; a side gap (SG) between the MP and the SS on multiple sides of the MP; and a leading gap (LG) between the MP and the LS.

9 . The device of claim 8 , wherein a height of the WG is greater than the eTHd height of the HS, which is configured to increase an electrical contact area between the HS and MP for a bias current flow.

10 . The device of claim 8 , wherein a thickness of the first part of the WG is uniform across the ABS plane to the eTHd height, and wherein a thickness of the second part of the WG increases with the height of the WG and is based on a shape of the HS.

11 . The device of claim 8 , wherein the LG and the SG comprise an electrical insulator material comprising aluminum oxide (Al 2 O 3 ).

12 . The device of claim 8 , wherein the LG and the SG comprise an electrical conductor comprising Ruthenium (Ru) or a Nickel-Chromium (NiCr)/Ruthenium (Ru) multilayer.

13 . A method for manufacturing a write head for a disk drive, the method comprising:
providing a main pole (MP) configured to provide a magnetic flux to a recording medium; disposing a trailing shield (TS) comprising a hot seed (HS) and write shield (WS) to collect a portion of the flux from the MP; disposing a write gap (WG) between the MP and TS, wherein the WG comprises a non-magnetic electrically conductive material; providing each of a side shield (SS), a leading shield (LS), and a write shield (WS) to prevent magnetic flux from reaching the medium bits away from the MP; disposing a side gap (SG) between the MP and the SS; and disposing a leading gap (LG) between the MP and the LS.

14 . The method of claim 13 , wherein a length of the WG is about equal to a length of the HS.

15 . The method of claim 13 , wherein a height of the WG is greater than an eTHd height of the HS, which is configured to increase an electrical contact area between the HS and MP for a bias current flow.

16 . The method of claim 15 , wherein the WG comprises a first part extending an air-bearing surface (ABS) plane of the write head to a top of the eTHd height and a second part extending from the top of the eTHd height.

17 . The method of claim 16 , wherein a thickness of the first part of the WG is uniform across the ABS plane to the eTHd height, and wherein a thickness of the second part of the WG increases with the height of the WG and is based on a shape of the HS.

18 . The write head of claim 1 , wherein the LG and the SG comprise an electrical insulator material comprising aluminum oxide (Al 2 O 3 ) or an electrical conductor comprising Ruthenium (Ru) or a Nickel-Chromium (Chromium) Ru (NiCr/Ru) multilayer.

Assignees

• Headway Tech Inc

Inventors

• Sayed Shehrin
• Liu Yue
• Chen Wenyu
• Ren Haowen
• Liu Kowang
• Tang Yuhui

Classifications

• G11B5/1278

  specially adapted for magnetisations perpendicular to the surface of the record carrier · CPC title

• G11B5/3116 Primary

  Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks (G11B5/3113, G11B5/245 take precedence) · CPC title

• G11B5/012 Primary

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