Read Rite Corporation

Western Digital (Fremont), Inc.

Stmicroelectronics S.r.l.

William D Jensen

Hugh Craig Hiner

Mark David Thomas

Durga P Ravipati

Yiming Huai

Xizeng Shi

Kyusik Sin

Matthew R Gibbons

Lien-Chang Wang

Billy Wayne Crue

Carlos Corona

Roberto Bez

Giulio Casagrande

Yun-Lin Hsiao

Durga I Ravipati

Marco Pasotti

Yingjian Chen

Paolo Giuseppe Cappelletti

Yugang Wang

Zhupei Shi

Francis H Liu

Hua-Ching Tong

Billy W Crue, Jr

Zi-Wen Dong

Chester Xiaowen Chien

Eric R Katz

Xizeng (Stone) Shi

Joyce Thompson

Paolo Cappeletti

Lein-Chang Wang

In a method and system for reducing power consumed by a magnetic memory, magnetic memory cells are coupled to a bit line and are associated with a plurality of digit lines. A bit line current is provided in the bit line. Digit currents are provided in parallel in the digit lines at substantially the same time as the bit line current. The digit and bit line currents allow the magnetic memory cells to be written to a plurality of states in parallel.

Method and system for controlling MRAM write current to reduce power consumption

A magnetic random access memory (MRAM) device has increased &#x394;R/R for sensing a state of a pin-dependent tunneling (SDT) device. The MRAM device includes plural transistors connected to a read line for sensing the state of the SDT device. Plural transistors lower an underlying resistance during reading, increasing &#x394;R/R. The plural transistors can share a source region.

Magnetic memory cell with plural read transistors

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

An inductive transducer having first and second magnetic pedestals disposed between first and second magnetic pole layers and adjacent to a media-facing surface, the pedestals separated by a submicron, nonmagnetic gap. The first pedestal extends less than the second pedestal from the media-facing surface, defining a short throat height. The second pedestal extends further to provide sufficient area for stitching to the second pole layer. The stitching and the thickness provided by the pedestals allow plural coil layers to be disposed between the pole layers, and the second pedestal, as well as other features, can be defined by high-resolution photolithography. The two coil layers have lower resistance, lower inductance and allow the pole layers to be shorter, improving performance. All or part of either or both of the pedestals may be formed of high magnetic saturation material, further enhancing performance.

Inductive transducer with stitched pole tip and pedestal defining zero throat height

A method and structure for providing a tunneling magnetoresistive (TMR) element is disclosed. The method and structure include providing a TMR layer that includes a first magnetic layer, a second magnetic layer and a first insulating layer disposed between the first magnetic layer and the second magnetic layer. The method and structure also include providing a first material and a protective layer. The first material allows electrical contact to be made to the tunneling magnetoresistive layer and is disposed above the tunneling magnetoresistive layer. The first material is capable of being undercut by an plasma etch without exposing a portion of the tunneling magnetoresistive layer under a remaining portion of the first material. The second protective layer covers a portion of the tunneling magnetoresistive sensor and a portion of the first material. In one aspect, the method and structure also include providing a second material disposed between the tunneling magnetoresistive layer and the first material. The second material allows electrical contact to be made to the tunneling magnetoresistive layer and is resistant to removal by the plasma etch.

Method and system for providing a self-aligned electrical contact for a TMR element

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 magnetic head includes first and second pole tips separated by a nonmagnetic gap layer. The right side walls of the first and second pole tips are vertically aligned. Similarly, the left side walls of the first and second pole tips are vertically aligned. The side fringing flux is substantially reduced resulting in a magnetic head capable of writing data tracks with well defined boundaries. The fabrication of the magnetic head begins with forming a stack of layers on a substrate. The stack of layers includes a nonmagnetic layer sandwiched between the first pole tip layer and a sacrificial layer which is preferably made of a metal. A protective layer, such as alumina, is then deposited over and around the stack of layers. After planarization and ion milling, the sacrificial layer is exposed. The sacrificial layer is then etched away leaving a volume of space in the protective layer and above the gap layer. An inductive coil with associated dielectric layers are then deposited above the first pole layer. The second pole layer is thereafter deposited over the inductive coil and into the volume of space resulting in the first and second pole tips having vertically aligned side walls.

Thin film magnetic head with self-aligned pole tips

A magnetic read/write head having improved thermal characteristics. The read/write head includes a read element and a write element formed there over. The read element includes a read sensor embedded within a dielectric material and sandwiched between first and second shields. The write element includes first and second poles joined to form a yoke. The yoke is closed at one end and defines a write gap at the other. A coil having windings which extend through the yoke generates a magnetic flux within the yoke. This magnetic flux causes a magnetic fringe field at the location of the write gap, the fringe field being capable of imparting a magnetic signal onto a passing magnetic medium. The coil sits atop a thermally conductive, electrically insulating material which electrically isolates the coil from surrounding structure. When a current flows through the coil, heat will be generated. Such heat, which could be detrimental to read performance, is conducted through the thermally conductive material out of the yoke and away from the write element. The thermally conductive material provides a large heat sink for dissipation of the heat.

Magnetic write element having a thermally dissipative structure

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 magnetic head includes aligned pole tips and a coil proximally disposed between a pair of first and second magnetic yoke layers which define a closed magnetic path with a transducing gap. The second magnetic yoke layer includes a flat geometry with a substantially level cross-sectional profile. The second yoke layer with less curvature results in less mutual inductance with the coil. Furthermore, the coil can be closely positioned between the first and second yoke layer, thereby allowing the coil to be more efficient in inducing magnetic flux in the yoke layers during data writing, and allowing the intercepted flux to induce current into the coil during data reading if the magnetic head is used as an inductive head.

Inductive write head formed with flat yoke and merged with

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

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Fremont, CA, United States of America

William D Jensen