Seagate Technology Incorporated

Magnetic Peripherals Inc.

Charles H Tolman

Gregory S Mowry

James F Dolejsi

Peter I Bonyhard

William P Wood

Declan Macken

Nurul Amin

Venkateswara R Inturi

Ibro Tabakovic

Lin Zhou

Steve C Riemer

Steven B Slade

Peter K George

Martin Louis Plumer

Alan Biggar Johnston

Michael M Collver

Simon H Liao

Terry B Mitchell

Greogory S Mowry

In a method of manufacturing a top pole of a write element for use in a disc drive storage system, a first trench is formed on a top surface of a bottom pole, the first trench includes a first opening defined by opposing first side walls and an exposed portion of the top surface located therebetween. Next, a second trench is formed within the first trench. The second trench includes a second opening defined by opposing second side walls formed adjacent the first side walls and a gap member formed on the exposed portion of the top surface of the bottom pole between the second side walls. Finally, a top pole is formed in the second opening, which is narrower than the first opening.

Narrow top pole of a write element

A method of making a magnetoresistance sensor which detects stored information from a medium and which provides an output voltage to a auxiliary circuitry is disclosed. The method comprises sputtering a bias layer in a sputtering gas mixture of nitrogen and argon. A spacer layer is also formed in a sputtering gas mixture of nitrogen and argon. Finally, an MR magnetic layer is formed. The spacer layer is positioned between the bias layer and the magnetic layer. The output voltage is provided to auxiliary circuitry when a current flows through the MR magnetic layer.

Method of making an improved MR sensor

A magnetic recording head has a magnetic pole tip and a seed layer upon which the magnetic pole tip is formed. The seed layer is preferably formed of a high magnetic moment material having a saturation magnetization of at least 1.8 Tesla and a high resistance to corrosion. In preferred embodiments of the present invention, the seed layer is preferably formed of 2.1 Tesla Fe Co Ni , 1.8 Tesla Fe Ni Co Tesla Fe Cr , or 1.9 Tesla Fe Co Cr , wherein the subscripts indicate a preferred range of atomic percentages for each element in the given alloy.

High magnetic moment seed layer materials for writer pole tips

A shield for a read element of a magnetic recording head is disclosed. The shield includes a first and a second triangular shaped closure magnetic domains positioned approximate a top surface of the shield such that a first surface of each of the first and second magnetic domains are formed by a portion of a first side of the shield and a second side of the shield, respectively. The shield also includes a third and a fourth triangular shaped closure magnetic domains positioned approximate the bottom surface of the shield. A first surface of the third and fourth magnetic domains are formed by a portion of the first side and the second side of the shield, respectively. A first magnetic domain wall is positioned between the first and second triangular shaped closure magnetic domains, while a second magnetic domain wall is positioned between the third and fourth triangular shaped closure magnetic domains.

Magnetic read element shield having dimensions that minimize domain wall movement

A magnetoresistive sensor for detecting stored information from a magnetic medium and for providing an output voltage to auxiliary circuitry is disclosed. The magnetoresistive sensor includes a magnetoresistive magnetic layer formed from a magnetic material, the magnetic layer having a magnetization, a resistivity and a thickness. A resistance of the magnetic layer equals the resistivity of the layer divided by the thickness of the layer. The magnetic sensor also comprises a bias layer having a resistivity, a thickness and a saturation inductance. A resistance of the bias layer equals the resistivity of the layer divided by the thickness of the layer. The resistance of the bias layer is in parallel with the resistance of the magnetic layer. The saturation inductance of the bias layer helps to bias the magnetic layer from a rest position to a magnetized position. A spacer layer is positioned between the magnetic layer and the bias layer. The spacer layer has a resistivity and a thickness. A resistance of the spacer layer equals the resistivity of the layer divided by the thickness of the layer. The resistance of the spacer layer is in parallel with both the resistances of the magnetic layer and the bias layer. The parallel resistances of the bias layer and the spacer layer is at least twice as large as the resistance of the magnetic layer such that at least two-thirds of the current flows through the magnetic layer and at most one-third of the current flows through the combination of the bias layer and the spacer layer.

MR sensors with selected resistances for the sensing and biasing layers

A magnetic pole assembly for a transducer includes a first pole piece having first and second arms joined to form front and back regions. The first and second arms are spaced between the front and back regions to form a region of low leakage-flux density. A second pole piece having front and back regions lies partly in the region of low leakage-flux density between the first and second arms of the first pole. The back region of the second pole is joined to the back region of the first pole, and the front regions of the first and second poles confront to form a gap. In one embodiment, the first and second poles are each formed of first and second portions with the first portion of the first pole and the second portion of the second pole formed in a first thin-film layer and the second portion of the first pole and the first portion of the second pole formed in a second thin-film layer spaced apart and substantially parallel to the first layer. Vias join the first and second portions of the poles together as well as the back portions of the poles. An inductive coil has a plurality of convolutions lying between the two layers, each convolution passing between the poles twice.

Method of making inductive transducer with closed-loop pole

A disc drive recording head which senses magnetic flux from a storage medium includes an MR sensor positioned on a trailing surface of a disc drive slider. First and second electrical contacts connect the MR sensor to first and second pads positioned on the trailing surface of the MR slider and minimizes an inductive voltage induced from the storage medium during the sensing of the magnetic flux.

Contact scheme for minimizing inductive pickup in magnetoresistive read

An MR sensor having improved current density distribution, reduced overall resistance and a substantially planar surface is disclosed. The MR sensor includes an MR layer having first and second outer regions and an active region located between the first and second outer regions. A first permanent magnet region is formed upon the first MR layer outer region and defines a first boundary of the MR layer active region. A second permanent magnet region is formed upon the second MR layer outer region and defines a second boundary of the MR layer active region so that a gap region is positioned at least partially between the first and second permanent magnet regions. A spacer layer is formed on the MR layer active region between the first and second permanent magnet regions. A soft adjacent layer is formed in the active region and upon the spacer layer, and, in some preferred embodiments, also at least partially upon the permanent magnet region.

Method of making a magnetoresistive sensor

Inductive transducer with closed-loop pole circumscribing I-shaped pole

Magnetoresistive sensor with improved performance and processability

A magnetoresistive sensor having a magnetization vector M and a current density vector J which form an angle of approximately 45.degree.. Magnetic flux, which enters an active region of the magnetoresistive sensor approximately perpendicular to the magnetization vector M, propagates across the active region with substantially constant length thereby producing a rectangular shaped read sensitivity function. The current density vector J is directed with electrical contacts adjacent the active region which have high resistance regions and low resistance regions.

Magnetoresistive sensor with electrical contacts having variable

An inductive thin film magnetic head carried on a substrate having a reduced susceptibility to the 'glitch' effect or 'remote read' effect. The inductive thin film head uses a three point approach using hard axis only drive fields, narrow paddles and shortened pole tips which are spaced apart from a saw alley when the substrate is sliced.

Inductive thin film head having improved readback characteristics

A magnetoresistive sensor element having bottleneck shaped ends. The sensor element has a highly stable, single domain central region, which eliminates Barkhausen noise.

Bottleneck magnetoresistive element

Ferromagnetic cobalt-iron (CoFe) is electrodeposited on a conductive substrate to form a CoFe thin film. The wet electrodeposition process disclosed involves use of a relatively low toxic plating bath solution in which the constituents cobalt and iron are introduced as soluble salts. A lesser amount of iron than cobalt is used to develop an approximately 90% cobalt to 10% iron ratio in the thin film. The plating solution also has sodium saccharin, dodecyl sodium sulfate and wetting and buffering agents. The CoFe thin film that results from using the disclosed process has near zero magnetostriction, acceptable permeability for use as a magnetic head, a highly stabilized magnetic domain and approximately twice the saturation moment of Permalloy. Magnetic heads fabricated from such film are well suited for use with high coercivity media for high density recording.

Growing community of inventors

Bloomington, MN, United States of America

Charles H Tolman