Read Rite Corporation

Western Digital (fremont), Inc.

Durga P Ravipati

William D Jensen

Yiming Huai

Yong Shen

Hugh Craig Hiner

Mark David Thomas

Carlos Corona

Lien-Chang Wang

Steven C Rudy

Billy Wayne Crue

Ut Tran

Daniel A Nepela

Samuel Wonder Yuan

William C Cain

Marcos Moises Lederman

Yunju Ra

Lein-Chang Wang

A magnetic head is fabricated by providing a substrate with a planar surface, forming at least one cavity in the planar substrate, depositing a second yoke layer in the cavity, forming a second pole tip in the cavity in contact with the second yoke layer, patterning an inductive coil in the cavity, depositing a gap layer over the second pole tip, sputtering a first pole tip over the gap layer, etching the first and second pole tips and the gap layer to form a stack of layers, depositing a protective layer over the stack of layers, leveling the protective layer to expose the first pole tip, and patterning a first yoke layer in contact with the first pole tip.

Method of making a magnetic head with aligned pole tips

A magnetic head includes pole tips with aligned sidewalls and a low head profile. The aligned sidewalls are formed by depositing a stack of pole tip layers on a substrate. The stack of layers are etched through a common overlying mask. The stack of layers is covered over and around with a protective layer which is then planarized such that the stack of layers is exposed. The protective layer is etched to a predetermined thickness above the substrate, which is thinner than the thickness of the stack of layers. An inductive coil layer is deposited on the etched protective layer and covered with an overlying magnetic yoke layer which is dielectrically separated from the coil layer. The yoke layer thus formed assumes a low profile curvature due to the thin structure of the protective layer on the substrate. As a consequence, the overall stack height of the magnetic head is reduced, thereby reducing the inductance of the overlying yoke layer and further alleviating the step coverage problem of the magnetic head during fabrication.

Magnetic head with low stack height and self-aligned pole tips

A thin film head apparatus and method for forming such a thin film head. In one approach, the present invention recites forming a cavity in a dielectric layer. Next, a layer of high magnetic field saturation (HBsat) material is sputter-deposited over the dielectric layer such that the HBsat material is deposited into the cavity formed in the dielectric layer. The cavity in the dielectric layer functions as a mold or &ldquo;stencil&rdquo; for the HBsat material. The HBsat material deposited into the cavity is used to form the first core of a thin film head. After the formation of the first core of the thin film head, a gap layer of material is deposited above the dielectric layer and above the first core. Next, a layer of HBsat material is sputter-deposited above the gap layer of material and above the first core of the thin film head. The layer of HBsat material disposed above the gap layer of material and above the first core is used to form the second core of the thin film head. Hence, this invention forms first and second cores of a thin film head using sputter deposition processes. As a result, selected HBsat materials which were not well suited to conventional thin film head formation methods can now be used to form the cores of thin film head structures.

Dielectric stencil-defined write head for MR, GMR, and spin valve high density recording heads

A magnetoresistive sensor including a magnetoresistive (MR) sensing element, a nonmagnetic layer ('spacer') contacting the magnetoresistive sensing element; a first antiferromagnetic (AFM) layer contacting the nonmagnetic layer such that the nonmagnetic layer is sandwiched between the magnetoresistive sensing element and the antiferromagnetic layer; a ferromagnetic soft adjacent layer (SAL) contacting the antiferromagnetic layer such that the antiferromagnetic layer is sandwiched between the nonmagnetic layer and the soft adjacent layer; and a second antiferromagnetic layer contacting the SAL such that the SAL is sandwiched between the first and second antiferromagnetic layers. The two antiferromagnetic layers provide a stronger pinning effect. In one embodiment of the invention, the magnetoresistive sensing element is an anisotropic magnetoresistive (AMR) sensing element comprising a soft ferromagnetic layer. In another embodiment of the invention, the magnetoresistive sensing element is giant magnetoresistive (GMR) sensing element comprising a plurality of layers. The bias scheme can be non-symmetric, or may be symmetric around the magnetoresistive sensing element. An exchange biased bilayer (AFM/SAL) can have a multilayered structure such as AFM/SAL/AFM/SAL. . . . In this configuration, the SAL layer can be thin, so that a high exchange field with a high resistance can be obtained.

Magnetoresistive sensor with pinned SAL

A magnetic head includes first and second pole tip layers separated by a nonmagnetic gap layer. The pole tips are made of a high magnetic moment material. The right side walls of the first and second pole tips are vertically aligned with each other. Similarly, the left side walls of the first and second pole tips are vertically aligned with one another. The side fringing flux from one pole tip to another is substantially reduced resulting in a magnetic head capable of writing data tracks with well defined boundaries. The possibility of the pole tips operating in magnetic saturation is reduced because the pole tips, formed of high magnetic moment material, is capable of accommodating high coercive force. The magnetic head can be fabricated as an inverted head or a non-inverted head capable of writing on magnetic media with high coercivity and at a high data transfer rate.

Magnetic head with aligned pole tips and pole layers formed of high

A method of making a magnetic head which includes first and second pole tip layers separated by a nonmagnetic gap layer includes making the pole tips of a high magnetic moment material. The right side walls of the first and second pole tips are vertically aligned with each other. Similarly, the left side walls of the first and second pole tips are vertically aligned with one another. The side fringing flux from one pole tip to another is substantially reduced resulting in a magnetic head capable of writing data tracks with well defined boundaries. The possibility of the pole tips operating in magnetic saturation is reduced because the pole tips, formed of high magnetic moment material, is capable of accommodating high coercive force. The magnetic head can be fabricated as an inverted head or a non-inverted head capable of writing on magnetic media with high coercivity and at a high data transfer rate.

Method of making a magnetic head with aligned pole tips and pole layers

A magnetoresistive read transducer includes a magnetoresistive (MR) layer having end regions spaced by a central active region. A pair of hard magnetic layers provide longitudinal magnetic bias to the MR layer, with each of the hard magnetic bias layers disposed in contact with one of the end regions of the MR layer. A pair of electrical lead members are disposed in contact with the end regions of the MR layer and with the hard magnetic bias layers. The hard magnetic bias layers and the electrical lead members are deposited, followed by selective removal of portions of the lead members to expose the edges of the hard bias material.

Thin film magnetoresistive device having contiguous magnetoresistive,

A magnetoresistive read transducer includes a magnetoresistive layer that is sandwiched between a pair of laminated magnetic shields. Each laminated magnetic shield includes at least two layers of ferromagnetic material spaced by a layer of non-magnetic material. The respective magnetization vectors of uniaxial anisotropy in the shields are opposite to each other. The magnetization vectors in the two ferromagnetic layers form a closed magnetic path which is substantially perpendicular to the surfaces of the layer interfaces. The magnetic pattern thus formed is highly stable, so that the magnetoresistive layer generates output signals with low Barkhausen noise and further allows the transducer to interact with recording media having high linear recording density.

Magnetoresistive transducer having laminated magnetic shields

A magnetoresistive spin valve giant magnetoresistive (GMR) transducer includes a magnetoresistive (MR)/GMR multi-layer with end portions spaced by a central active portion. A pair of electrical lead layers conducts electrical bias current to the transducer. Each electrical lead layer forms abutting junctions in contact with respective end portion of the MR/GMR layers. The longitudinal bias for the MR/GMR layers is provided by a pair of magnetic bias layers. Each magnetic bias layer is disposed in contact with a respective end portion of the MR/GMR layers. Bias current flows into the MR/GMR layers directly through the abutting junctions, allowing the magnetic bias to assume a different bias path through the end portions of the MR/GMR layers. The MR/GMR transducer allows both the electrical and magnetic biases to be optimally designed, without any constraint of one restricting the other, as the two biases often pose conflicting requirements. In addition, the direct electrical current path provides lower electrical resistance and heat dissipation which are of substantial benefit to the performance and reliability of the transducer.

Spin-valve GMR sensor with inbound exchange stabilization

A spin valve magnetoresistive sensor includes a substrate and a layered structure formed on the substrate. The layered structure includes a pair of thin film layers of ferromagnetic material separated from each other by a nonmagnetic spacer. The direction of magnetization of one of the thin film layers is pinned by a first permanent magnet layer. A second permanent magnet layer is located adjacent to the other of the thin film layers for longitudinal biasing purposes. The first permanent magnet layer has significantly higher coercivity than the second permanent magnet layer.

Spin valve magnetoresistive transducers having permanent magnets

A magnetoresistive read transducer includes a magnetoresistive (MR) layer having end regions spaced by a central active regions. A pair of hard-magnetic layers provide the longitudinal magnetic bias to the magnetoresistive layer. Each of the hard-magnetic layers is disposed in contact with one of the end regions of the magnetoresistive layer. In addition, a pair of electrical leads provide the bias current to the magnetoresistive layer. Each of the electrical leads is also disposed in contact with one of the end regions of the magnetoresistive layer. This arrangement enable the transducer of the present invention with the most optimal design. In essence, electrical current directly passes through the central active region of the magnetoresistive layer via the electrical leads as a low electrical resistance path. Magnetic flux of the longitudinal bias directly passes through the central active region of the magnetoresistive layer with a reduced probability of magnetic discontinuity.

Magnetoresistive structure with contiguous junction hard bias design

A magnetoresistive transducer includes a magnetoresistive layer having end portions spaced by a central active portion. The longitudinal bias for the magnetoresistive layer is cooperatively furnished by a pair of hard magnetic bias regions. Each of the two hard magnetic bias regions includes a plurality of magnetized layers and each bias region is disposed in contact with one of the end portions of the magnetoresistive transducer. The magnetic flux required for the magnetoresistive layer to maintain a single domain state is adequately provided by the hard magnetic bias regions. In one embodiment, a substantially uniform thickness for the entire transducer is achieved, allowing the longitudinal bias to be continuously supplied to the magnetoresistive layer. In another embodiment, thinner hard magnetic bias regions provide improved step coverage for the second read gap thereby increasing yield. Also the thinner hard magnetic bias regions provide a significant increase of planarization of the write poles.

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Saratoga, CA, United States of America

Durga P Ravipati