US 7,292,409 B1 · Magnetic head with thin trailing pedestal layer · patentgrep

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Abstract

A magnetic head for a disk drive is disclosed that has a first soft magnetic pole layer disposed in the head adjacent to a medium-facing surface and extending perpendicular to the medium-facing surface; a second soft magnetic pole layer disposed closer than the first pole layer to the trailing end, the second pole layer magnetically coupled to the first pole layer in a backgap region; a soft magnetic pedestal adjoining the second pole layer, disposed closer than the second pole layer to the medium-facing surface and extending less than the second pole layer extends from the medium-facing surface, the pedestal separated from the first pole layer by a nonferromagnetic gap, the pedestal having a thickness that is less than four hundred and fifty nanometers between the gap and the second pole layer. Longitudinal and perpendicular recording embodiments are disclosed, as well as solenoidal, single-layer and dual-layer reversed-current coil structures.

Claims38

Dependent claims

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a soft magnetic pedestal adjoining the second pole layer, the soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the soft magnetic pedestal separated from the first soft magnetic pole layer by a nonferromagnetic gap, the soft magnetic pedestal having a thickness that is less than four hundred and fifty nanometers between the nonferromagnetic gap and the second soft magnetic pole layer;
and
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers, the conductive section being part of a coil;
and
wherein the magnetic head has at least one set of characteristics selected from a group consisting of the following sets of characteristics:
(a) the conductive section is ferromagnetic and the coil substantially encircles the second soft magnetic pole layer;
(b) the coil includes a first plurality of conductive sections that are disposed between and electrically isolated from the first and second soft magnetic pole layers the first plurality of conductive sections disposed in a first layer, extending parallel to each other, and each terminating in a conductive portion that is disposed in the first layer and extends transversely to the first plurality of conductive sections;
and
(c) the coil includes a second plurality of conductive sections that are disposed between and electrically isolated from the first and second soft magnetic pole layers, the conductive sections disposed in a second layer, extending parallel to each other, and having a different length measured in a direction parallel to the medium-facing surface.

8 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a first soft magnetic pedestal adjoining the first soft magnetic pole layer, the first soft magnetic pedestal including a region that extends less than the first soft magnetic pole layer extends from the medium-facing surface;
a second soft magnetic pedestal adjoining the second soft magnetic pole layer, the second soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal separated from the first pedestal by a nanoscale nonferromagnetic gap, the second soft magnetic pedestal having a thickness of less than four hundred fifty nanometers between the nanoscale nonferromagnetic gap and the second soft magnetic pole layer, the second soft magnetic pedestal and the first soft magnetic pedestal having track widths that are substantially aligned for a distance that is less than nine hundred nanometers;
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers, the conductive section being part of a coil that substantially encircles the second soft magnetic pole layer;
and
wherein the magnetic head has at least one set of characteristics selected from a group consisting of the following sets of characteristics:
(a) the conductive section is ferromagnetic;
(b) the coil includes a first plurality of conductive sections that are disposed between and electrically isolated from the first and second soft magnetic pole layers the first plurality of conductive sections disposed in a first layer, extending parallel to each other, and each terminating in a conductive portion that is disposed in the first layer and extends transversely to the first plurality of conductive sections;
and
(c) the coil includes a second plurality of conductive sections that are disposed between and electrically isolated from the first and second pole layers, the second plurality of conductive sections disposed in a second layer, extending parallel to each other, and having a different length measured in a direction parallel to the medium-facing surface.

8 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a first soft magnetic pedestal adjoining the first soft magnetic pole layer, the first soft magnetic pedestal including a region that extends less than the first soft magnetic pole layer extends from the medium-facing surface;
a second soft magnetic pedestal adjoining the second soft magnetic pole layer, the second soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal separated from the first pedestal by a nanoscale nonferromagnetic gap the second soft magnetic pedestal having a thickness of less than four hundred fifty nanometers between the nanoscale nonferromagnetic gap and the second soft magnetic pole layer, the second soft magnetic pedestal and the first soft magnetic pedestal having track widths that are substantially aligned for a distance that is less than nine hundred nanometers;
and
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers the conductive section being part of a coil that substantially encircles the second pole soft magnetic layer;
and
wherein the magnetic head has at least one set of characteristics selected from a group consisting of the following sets of characteristics:
(a) the second soft magnetic pole layer has a leading surface and a trailing surface, the trailing surface having a flat area disposed approximately midway between the medium-facing surface and the backgap region, the leading surface having a curved area disposed closest to the flat area;
(b) the second soft magnetic pole layer has a trailing surface that is disposed distal to the first soft magnetic pole layer, the trailing surface having a plurality of curved sections separated by a flat, polished section;
and
(c) the first and second soft magnetic pedestals include a high magnetic saturation material.

9 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and terminating adjacent to the medium-facing surface in a return pole tip;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a soft magnetic pedestal adjoining the second soft magnetic pole layer, the soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal terminating adjacent to the medium-facing surface in a write pole tip that is at least two orders of magnitude smaller than the return pole tip, the soft magnetic pedestal having a thickness that is less than two hundred and fifty nanometers between a gap and the second soft magnetic pole layer;
and
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers, the conductive section being part of a coil;
and
wherein the magnetic head has at least one set of characteristics selected from a group consisting of the following sets of characteristics:
(a) the coil substantially encircles the backgap region;
(b) the coil includes a first plurality of conductive sections that are disposed between and electrically isolated from the first and second soft magnetic pole layers, the first plurality of conductive sections disposed in a first layer, extending parallel to each other, and each terminating in a conductive portion that is disposed in the first layer and extends transversely to the first plurality of conductive sections;
(c) the coil includes a second plurality of conductive sections that are disposed between and electrically isolated from the first and second soft magnetic pole layers, the second plurality of conductive sections disposed in a second layer, extending parallel to each other, and having a different length measured in a direction parallel to the medium-facing surface;
and
(d) the coil includes a third plurality of conductive sections that are disposed between and electrically isolated from the first and second pole soft magnetic layers, and an inorganic nonmagnetic insulating material is disposed between the third plurality of conductive sections.

9 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and terminating adjacent to the medium-facing surface in a return pole tip;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a soft magnetic pedestal adjoining the second soft magnetic pole layer, the soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal terminating adjacent to the medium-facing surface in a write pole tip that is at least two orders of magnitude smaller than the return pole tip, the soft magnetic pedestal having a thickness that is less than two hundred and fifty nanometers between a gap and the second soft magnetic pole layer;
and
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers;
and
wherein the magnetic head has at least one set of characteristics selected from a group consisting of the following sets of characteristics:
(a) the second soft magnetic pole layer has a leading surface and a trailing surface, the trailing surface having a flat area disposed approximately midway between the medium-facing surface and the backgap region, the leading surface having a curved area disposed closest to the flat area;
(b) the second soft magnetic pole layer has a trailing surface that is disposed distal to the first soft magnetic pole layer, the trailing surface having a plurality of curved sections separated by a flat, polished section;
and
(c) the pedestal includes a high magnetic saturation material.

8 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a first soft magnetic pedestal adjoining the first soft magnetic pole layer, the first soft magnetic pedestal including a region that extends less than the first soft magnetic pole layer extends from the medium-facing surface;
a second soft magnetic pedestal adjoining the second soft magnetic pole layer, the second soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal separated from the first soft magnetic pedestal by a nanoscale nonferromagnetic gap, the second soft magnetic pedestal and the first soft magnetic pedestal having track widths that are substantially aligned for a distance that is less than nine hundred nanometers;
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers;
wherein the conductive section is part of a coil that substantially encircles the second soft magnetic pole layer;
and
wherein the conductive section is part of a coil that includes a plurality of conductive sections that are disposed between and electrically isolated from the first and second pole layers, the conductive sections disposed in a layer, extending parallel to each other, and each terminating in a conductive portion that is disposed in the layer and extends transversely to the conductive sections.

5 more elements

A magnetic head for writing information on a relatively-moving medium, the head having a leading end, a trailing end and a medium-facing surface, the head comprising:

a first soft magnetic pole layer disposed in the head adjacent to the medium-facing surface and extending substantially perpendicular to the medium-facing surface;
a second soft magnetic pole layer disposed closer than the first soft magnetic pole layer to the trailing end, the second soft magnetic pole layer magnetically coupled to the first soft magnetic pole layer in a backgap region that is removed from the medium-facing surface;
a first soft magnetic pedestal adjoining the first soft magnetic pole layer, the first soft magnetic pedestal including a region that extends less than the first soft magnetic pole layer extends from the medium-facing surface;
a second soft magnetic pedestal adjoining the second soft magnetic pole layer, the second soft magnetic pedestal disposed closer than the second soft magnetic pole layer to the medium-facing surface and extending less than the second soft magnetic pole layer extends from the medium-facing surface, the second soft magnetic pedestal separated from the first soft magnetic pedestal by a nanoscale nonferromagnetic gap, the second soft magnetic pedestal and the first soft magnetic pedestal having track widths that are substantially aligned for a distance that is less than nine hundred nanometers;
a conductive section that is disposed between and electrically isolated from the first and second soft magnetic pole layers;
wherein the conductive section is part of a coil that substantially encircles the second soft magnetic pole layer;
and
wherein the conductive section is part of a coil that includes a plurality of conductive sections that are disposed between and electrically isolated from the first and second pole layers, the conductive sections disposed in a layer, extending parallel to each other, and having a different length measured in a direction parallel to the medium-facing surface.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/788,766Filed 27 Feb 2004
Granted: 6 Nov 2007
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

G11B 5/3146
Including additional layers for improving the electromagnetic transducing properties of the basic structure, e.g. for flux coupling, guiding or…:…
G11B 5/17
Structure or manufacture of heads, e.g. inductive: construction or disposition of windings
G11B 5/3116
Details: shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect,…
G11B 5/3123
For reducing flux leakage between the electrical coil layers and the magnetic cores or poles or between the magnetic cores or poles: by using…

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