# US 7,073,250 B2 · Method of manufacturing thin film magnetic head having partial insulating layer formed on bottom pole layer through gap layer

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- Number: US 7,073,250 B2
- Document ID: US7073250B2
- Status: Granted
- Kind: B2
- Application number: 10/632,374
- Filed: 2003-08-01
- Published: 2004-02-05
- Granted: 2006-07-11
- Earliest claimed: 2000-09-11
- Assignees: Alps Electric Co., Ltd.
- Inventors: Sumihito Morita; Naruaki Oki; Toshinori Watanabe; Hiroko Shinozaki
- Web page: https://patentgrep.com/patent/US7073250B2

## CPC

- G11B 5/313: {Disposition of layers}
- B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
- 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)}
- G11B 5/09: Digital recording
- G11B 5/3967: {Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read (G11B5/3906 takes precedence)}
- Y10T 29/49032: Fabricating head structure or component thereof
- Y10T 29/49041: with significant slider/housing shaping or treating
- Y10T 29/49043: Depositing magnetic layer or coating
- Y10T 29/49048: Machining magnetic material [e.g., grinding, etching, polishing]
- Y10T 29/49052: by etching
- Y10T 29/4906: Providing winding
- Y10T 29/49064: by coating
- 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)
- B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A thin film magnetic head wherein a partial insulating layer is formed on a bottom pole layer with a gap layer provided therebetween, the gap depth Gd being regulated by the distance from a surface facing a recording medium to the partial insulating layer. A magnetic flux partially leaks from a tip region of an upper core layer to the bottom pole layer through the partial insulating layer to effectively suppress magnetic saturation of the tip region, thereby improving the NLTS characteristic and PW50 characteristic, and suppressing the occurrence of side fringing.

## Claims

### Claim 1

A method of manufacturing a thin film magnetic head comprising:
(a) the step of forming a bottom pole layer on a lower core layer with a predetermined length from a surface facing a recording medium in a height direction;
(b) the step of forming a first insulating layer on the bottom pole layer and the lower core layer, and then planarizing upper surfaces of the bottom pole layer and the first insulating layer to the same plane;
(c) the step of forming a nonmagnetic gap layer on at least the bottom pole layer;
(d) the step of forming a partial insulating layer on the bottom pole layer with the gap layer provided therebetween to start from a position at a predetermined distance from the surface facing the recording medium so that a gap depth is regulated by the predetermined distance, wherein the partial insulating layer is formed to extend from a top of the bottom pole layer to a top of the first insulating layer;
(e) the step of forming a coil layer on a portion of the first insulating layer which is behind the partial insulating layer in the height direction, and coating the coil layer with a second insulating layer; and
(f) the step of forming an upper core layer on the gap layer, the partial insulating layer and the second insulating layer, in which the upper core layer comprises a narrow tip region formed on the gap layer and the partial insulating layer to be exposed with a track width at the surface facing the recording medium, and a rear end region formed on the second insulating layer so that a width dimension in the track width direction gradually increases in a backward height direction from an end edge of the tip region.

### Claim 2 (depends on 1)

The method of manufacturing a thin film magnetic head according to claim 1, wherein the partial insulating layer comprises an organic insulating layer.

### Claim 3 (depends on 1)

The method of manufacturing a thin film magnetic head according to claim 1, further comprising the following step (g) between the steps (b) and (c), and the following step (h) used instead of the step (e):
(g) the step of partially cutting a top of the first insulating layer to form a coil forming surface behind the bottom pole layer in the height direction; and
(h) the step of forming a coil layer on the coil forming surface, and coating the coil layer with a second insulating layer.