# US 8,542,463 B2 · Non-uniform write gap perpendicular writer for shingle writing

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- Number: US 8,542,463 B2
- Document ID: US8542463B2
- Status: Granted
- Kind: B2
- Application number: 13/134,600
- Filed: 2011-06-10
- Published: 2012-12-13
- Granted: 2013-09-24
- Earliest claimed: 2011-06-10
- Assignees: Headway Technologies, Inc.
- Applicants: Lijie Guan
- Inventors: Lijie Guan
- Web page: https://patentgrep.com/patent/US8542463B2

## CPC

- 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)}
- C23C 14/06: characterised by the coating material ({C23C14/0021} , C23C14/04 take precedence)
- G11B 5/1278: {specially adapted for magnetisations perpendicular to the surface of the record carrier}
- G11B 5/3176: {Structure of heads comprising at least in the transducing gap regions two magnetic thin films disposed respectively at both sides of the gaps (G11B5/2455, G11B5/265 take precedence)}
- G11B 5/6082: {Design of the air bearing surface}
- G11B 5/84: Processes or apparatus specially adapted for manufacturing record carriers
- G11B 5/85: Coating a support with a magnetic layer by vapour deposition
- G11B 5/851: Coating a support with a magnetic layer by sputtering
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)
- C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04)

## Abstract

A PMR writer is disclosed that includes at least one of a recessed center section in the write pole trailing edge and a center recessed trailing shield to improve the field gradient at track edge. In all embodiments, there is a non-uniform write gap between the trailing edge and the trailing shield. The recessed portion of the write pole trailing edge and/or center recess of the trailing shield has a thickness from 10 to 40 nm in a down-track direction and a width in a cross-track direction of 20 to 200 nm. The distance between the center recess and a corner of the trailing edge is from 20 to 80 nm. A sequence of steps is provided to fabricate the two embodiments of the present invention.

## Claims

### Claim 1

A PMR writer for shingle writing, comprising:
(a) a write pole formed along an air bearing surface (ABS) with a leading edge and trailing edge formed parallel to a top surface of a substrate, and having two sides wherein each side intersects the trailing edge at a corner;
(b) a write gap formed on the trailing edge and having a non-planar top surface, comprising:
(1) a first end section formed parallel to the trailing edge and aligned above a portion of the write pole including a first corner;
(2) a second end section formed parallel to the trailing edge and aligned above a portion of the write pole including a second corner; and
(3) a convex curved shaped center section in the form of a single arc connecting the first and second end sections and wherein the center section is formed a greater distance from the trailing edge than the first and second end sections such that a variable first thickness of the write gap below the center section is greater than a fixed second thickness below the first and second end sections;
(c) a side gap that adjoins each side of the write pole and having a side formed substantially parallel to a nearest side of the write pole and located a gap distance therefrom;
(d) a side shield that adjoins said side of each side gap and interfaces with an overlying trailing shield; and
(e) the trailing shield that adjoins a top surface of each side shield and is formed on the top surface of the write gap.

### Claim 2 (depends on 1)

The PMR writer of claim 1 wherein the second thickness of the write gap is from 15 to 30 nm.

### Claim 3 (depends on 2)

The PMR writer of claim 2 wherein the center section has a width in a cross-track direction of about 20 to 200 nm and the variable first thickness of the write gap below the center section has a maximum value about 10 to 40 nm greater than the fixed second thickness.

### Claim 4 (depends on 1)

The PMR writer of claim 1 wherein the first and second end sections have a width in a cross-track direction of about 20 to 80 nm.

### Claim 5 (depends on 1)

The PMR writer of claim 1 wherein the center section has a semi-circular shape.