Perpendicular magnetic recording (PMR) write shield design with minimized wide adjacent track erasure (WATE)

• US 9,466,319 B1
• Filed: 09/08/2015
• Issued: 10/11/2016
• Est. Priority Date: 09/08/2015
• Status: Active Grant

• Current Assignee: Headway Technologies Incorporated (TDK Corporation)
• Original Assignee: Headway Technologies Incorporated (TDK Corporation)
• Inventors: Tang, Yuhui, Wei, Yaguang, Liu, Yue, Dovek, Moris, Liu, Xiaomin, Li, Feiyue, Wang, Po-Kang, Thomas, Luc
• Primary Examiner(s): EVANS, JEFFERSON A
• Application Number:
  US14/847,418
• Time in Patent Office: 399 Days
• Field of Search: 360/125.3
• US Class Current: 1/1
• CPC Class Codes: G11B 5/11 Shielding of head against electric or magnetic fields
• CPC Class Codes: G11B 5/112 Manufacture of shielding device
• CPC Class Codes: G11B 5/1278 specially adapted for magnetisations perpendicular to the surface of the record carrier
• 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
• CPC Class Codes: G11B 5/3143 including additional layers for improving the electromagnetic transducing properties of the basic structure, e.g. for flux coupling, guiding or shielding G11B5/3116, G11B5/312 take precedence
• CPC Class Codes: G11B 5/3146 magnetic layers
• CPC Class Codes: G11B 5/315 Shield layers on both sides of the main pole, e.g. in perpendicular magnetic heads
• CPC Class Codes: G11B 5/3163 Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers

Abstract

A Perpendicular Magnetic Recording (PMR) writer is disclosed with an all wrap around (AWA) shield design in which one or more of the leading shield, second trailing shield, and side shields consist of a high damping (HD) magnetic material having a damping constant ≧0.04. A first trailing shield between the write gap and second trailing shield is a 19-24 kG hot seed layer. The HD magnetic layer may be FeNiRe with a Re content of 3 to 15 atomic %. Preferably, the HD magnetic layer has a coercivity <50 Oe and is a 10-19 kG material. One or both of the main pole leading and trailing sides may be tapered. Wide adjacent track erasure is minimized while area density capability is maintained. In other embodiments, the HD magnetic material may be one of FeNiM, FeNM, FeCoM, or FeCoNiM where M is a 3d, 4d, or 5d transition metal.

Claims

1. A perpendicular magnetic recording (PMR) writer, comprising:

(a) a main pole comprised of a write pole portion having a leading side adjoining a lead gap, and with a leading edge at an air bearing surface (ABS), and having a trailing side adjoining a write gap, and a trailing edge at the ABS;

(b) a gap layer surrounding the main pole, the gap layer includes the lead gap, the write gap, and a side gap which contacts each of two sidewalls of the write pole portion wherein each sidewall is equidistant from a center plane that is aligned orthogonal to the ABS; and

(c) an all wrap around (AWA) shield structure wherein one or more of a leading shield, side shields, and a second trailing shield consist of a high damping (HD) magnetic layer having a damping constant α

of at least 0.04, comprising;

(1) the leading shield having a side that contacts the lead gap and contacts a bottom surface of the side shields along a first plane that is orthogonal to the center plane;

(2) a composite trailing shield wherein a first trailing shield made of a 19-24 kG hot seed layer adjoins a top surface of the write gap, and the second trailing shield adjoins a top surface of the hot seed layer, and contacts a top surface of the side shields at a second plane that is parallel to the first plane; and

(3) the side shields wherein a side shield on each side of the center plane has a side adjoining the side gap.

2. The PMR writer of claim 1 wherein the high damping magnetic layer is an alloy that is one of FeNiM, FeCoM, FeNM, and FeCoNiM where M is one of Re, Os, Ir, Rh, Ti, Ta, V, Cr, W, Mn, Mo, Cu, Zr, Nb, Hf, Ru, Pd, Pt, Ag, and Au.

3. The PMR writer of claim 2 wherein the high damping magnetic layer is FeNiRe wherein the Re content is from about 3 to 15 atomic %.

4. The PMR writer of claim 1 wherein the side shields consist of the HD magnetic layer, and the leading shield and the second trailing shield are made of FeCo, FeCoNi, or FeNi.

5. The PMR writer of claim 1 wherein the leading shield and the side shields consist of the HD magnetic layer, and the second trailing shield is made of FeCo, FeCoNi, or FeNi.

6. The PMR writer of claim 1 wherein each of the leading shield, side shields, and the second trailing shield consist of the HD magnetic layer.

7. The PMR writer of claim 1 wherein the high damping magnetic layer is a 10-19 kG material.

8. The PMR writer of claim 1 wherein a coercivity (Hc) of the high damping magnetic layer is less than 50 Oe.

9. The PMR writer of claim 1 wherein each of the sidewalls of the write pole portion proximate to the ABS is formed at an angle γ

of about 0 to 40 degrees with respect to the center plane, and each of the sidewalls of the write pole portion is formed at an angle δ

with respect to the center plane at a location proximate to a corner where the write pole portion intersects a back portion of the main pole, and δ

>

γ

.

10. The PMR writer of claim 9 wherein each side shield has a sidewall that follows a curvature of an adjacent write pole sidewall up to a point proximate to one of the corners.

11. The PMR writer of claim 1 wherein each of the sidewalls of the write pole portion proximate to the ABS is formed at an angle γ

of about 0 to 40 degrees with respect to the center plane, and each of the sidewalls of the write pole portion is formed at an angle θ

of about 90±

5 degrees with respect to the center plane at a location proximate to a corner where the write pole portion intersects a back portion of the main pole.

12. The PMR writer of claim 11 wherein each side shield has a first sidewall section that is substantially parallel to the write pole portion sidewall that is proximate to the ABS.

13. The PMR writer of claim 12 wherein each side shield further comprises a second sidewall section that is substantially parallel to the ABS and is connected to an end of the first sidewall section.

14. The PMR writer of claim 1 wherein one or both of the leading side and the trailing side are tapered in that a back end of the one or both leading side and trailing side is a greater distance than a front end at the ABS from a plane that bisects the main pole and is orthogonal to the center plane and to the ABS.

15. A method of forming an all wrap around (AWA) shield structure in a perpendicular magnetic recording (PMR) writer, comprising:

(a) providing a high damping (HD) magnetic layer having a damping constant α

of at least 0.04, the HD magnetic layer is formed on a substrate;

(b) forming an opening with a sidewall in each of two upper side shield portions of the HD magnetic layer wherein a bottom of the opening exposes a section of top surface on a leading shield portion of the HD magnetic layer, the sidewalls are equidistant from a center plane that intersects the bottom of the opening;

(c) conformally depositing a gap layer on the top surface of the leading shield portion and on the sidewalls within the opening to form a lead gap and side gaps, respectively;

(d) electroplating a main pole layer on the lead gap and side gaps such that the main pole layer fills the opening;

(e) performing a chemical mechanical polish (CMP) process to form top surfaces of the side gaps, main pole layer, and the upper side shield portions at a second plane that is orthogonal to the center plane;

(f) sequentially forming a write gap and then a first trailing shield that is made of a 19-24 kG hot seed layer on the main pole layer, side gaps, and adjacent sections of the upper side shield portions at the second plane, the write gap and first trailing shield each have a first cross-track width; and

(g) forming a second trailing shield on the first trailing shield, and on exposed portions of the upper side shield portions at the second plane.

16. The method of claim 15 wherein the HD magnetic layer is an alloy that is one of FeNiM, FeCoM, FeNM, and FeCoNiM where M is one of Re, Os, Ir, Rh, Ti, Ta, V, Cr, W, Mn, Mo, Cu, Zr, Nb, Hf, Ru, Pd, Pt, Ag, and Au.

17. The method of claim 16 in which the HD magnetic layer is FeNiRe wherein the Re content is from about 3 to 15 atomic %.

18. The method of claim 15 wherein the second trailing shield is made of FeCo, FeCoNi, or FeNi.

19. The method of claim 15 wherein the second trailing shield is a HD magnetic layer that is one of FeNiM, FeCoM, FeNM, and FeCoNiM where M is one of Re, Os, Ir, Rh, Ti, Ta, V, Cr, W, Mn, Mo, Cu, Zr, Nb, Hf, Ru, Pd, Pt, Ag, and Au.

20. The method of claim 15 further comprised of forming a taper on the main pole top surface before forming the write gap.

21. The method of claim 15 wherein the HD magnetic layer is a 10-19 kG material.

22. The method of claim 15 wherein a coercivity (Hc) of the HD magnetic layer is less than about 50 Oe.

23. The method of claim 15 further comprised of a lapping process to form an air bearing surface (ABS) that is orthogonal to the center plane and to the second plane, and exposes each of the main pole layer, side gaps, upper side shield portions, leading gap, leading shield portion, write gap, and first and second trailing shields at the ABS.

24. The method of claim 23 wherein the sidewalls of the upper shield portions proximate to the ABS are formed at an angle γ

of 0 to about 40 degrees with respect to the center plane.