Write Gap Structure for a Magnetic Recording Head

• US 20150002963A1
• Filed: 06/28/2013
• Published: 01/01/2015
• Est. Priority Date: 06/28/2013
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Tian, Wei, Yin, Huaqing, Xue, Jianhua, Dong, Yan, Mundenar, Joseph M.
• Granted Patent: US 9,318,131 B2
• Time in Patent Office: Days
• US Class Current: 360/235.4
• CPC Class Codes: G11B 5/23 Gap features G11B5/1871, G11B5/1875, G11B5/265, G11B5/29, G11B5/488 and subgroups, G11B5/4907 and subgroups, G11B5/4969 and subgroups take precedence
• CPC Class Codes: G11B 5/232 Manufacture of gap
• CPC Class Codes: G11B 5/3116 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

Abstract

The present application relates to a write gap structure for a magnetic recording head. In illustrated embodiments, the write gap structure includes multiple write gap segments along a beveled pole tip surface between a top edge and a bottom edge of the beveled pole tip surface to provide a narrow write gap proximate to the air bearing surface and a larger write gap behind the air bearing surface. In illustrated embodiments, the narrow write gap segment is formed between the beveled pole tip surface and a lower back surface of front shield and the larger write gap is formed between the beveled pole tip surface and an upper back surface of the front shield.

Claims

1. A write assembly comprising:

a write pole having a pole tip including a beveled pole tip surface having a bottom edge formed at an air bearing surface and a top edge spaced from the bottom edge;

a front shield spaced from the pole tip including an upper back surface and a lower back surface connected through a back edge located below the top edge of the beveled pole tip surface; and

a non-magnetic write gap including a proximal write gap segment located proximate to the air bearing surface having a proximal gap width extending between the beveled pole tip surface and the lower back surface of the shield and a distal write gap segment having a distal gap width larger than the proximal gap width extending between the beveled pole tip surface and the upper back surface of the shield.

2. The write assembly of claim 1 wherein the air bearing surface of the pole tip includes a leading edge and a trailing edge formed at the bottom edge of the beveled pole tip surface and the leading edge has a narrower cross-track width dimension than a cross-track width dimension of the trailing edge at the bottom edge of the beveled pole tip surface.

3. The write assembly of claim 1 in combination with a media having a soft under layer and a return pole to form a flux path between the write pole and the return pole through the soft under layer.

4. The write assembly of claim 1 wherein the lower back surface is conformal to the beveled pole tip surface to form a conformal gap along the proximal write gap segment.

5. The write assembly of claim 4 wherein the upper back surface is non-conformal to the beveled pole tip surface to form a non-conformal gap along the distal write gap segment.

6. The write assembly of claim 1 wherein the upper and lower back surfaces are connected through a back step connecting the upper back surface to the lower back surface.

7. The write assembly of claim 6 wherein the lower back surface is conformal with the beveled pole tip surface.

8. The write assembly of claim 7 wherein the upper back surface is non-conformal with the beveled pole tip surface.

9. The write assembly of claim 7 wherein the upper back surface is conformal with the beveled pole tip surface.

10. The write assembly of claim 1 wherein the upper and lower back surfaces of the front shield have different slope angles to define the proximal and distal gap widths.

11. The write assembly of claim 1 wherein the proximal gap width is less than 25 nm and the distal gap width is 25 nm or greater.

12. The write assembly of claim 1 wherein the proximal gap width is 20 nm or less and the distal gap width is more than 20 nm.

13. A write assembly comprising a write pole having a beveled pole tip surface;

a front shield spaced from the beveled pole tip surface; and

a non-magnetic write gap between the beveled pole tip surface and a back surface of the front shield having a write gap width less than 25 nm.

14. The write assembly of claim 13 wherein the write gap width is 20 nm or less.

15. The write assembly of claim 13 wherein the write gap includes a proximal gap width proximate to the air bearing surface of 20 nm or less and a distal gap width spaced from the air bearing surface below a top edge of the beveled pole tip surface greater than 20 nm.

16. The write assembly of claim 15 wherein the front shield includes an upper back surface and a lower back surface and a surface step connecting the upper and lower back surfaces and the proximal gap width extends between the beveled pole tip surface and the lower back surface and the distal gap width extends between the beveled pole tip surface and the upper back surface.

17. The write assembly of claim 15 wherein front shield includes an upper back surface and a lower back surface having different slope angles and the proximal gap width extends between the beveled pole tip surface and the lower back surface and the distal gap width extends between the beveled pole tip surface and the upper back surface.

20. The method of claim 17 wherein the step of fabricating the front shield comprises

depositing a seed layer on the first and second non-magnetic layers;

and

depositing a front shield material on the seed layer to form the upper and lower back surfaces of the front shield.

18. A method comprising:

depositing a first non-magnetic layer along a front beveled surface of a pole tip;

depositing a second non-magnetic layer on the first non-magnetic layer along the front beveled surface of the pole tip;

etching the second non-magnetic layer to remove a portion of the second non-magnetic layer from the first non-magnetic layer; and

fabricating the front shield on the first non-magnetic layer to form a lower back surface of the front shield and on the second non-magnetic layer to form an upper back surface of the front shield.

19. The method of claim 18 wherein the step of depositing the first non-magnetic layer and the second non-magnetic layer comprises depositing a first material to deposit the first non-magnetic layer and depositing a second material different from the first material to deposit the second non-magnetic layer.