Patents Represented by Attorney Ervin F. Johnston
  • Patent number: 7349180
    Abstract: First, second and third pole tip components of a write head are formed with the second pole tip located between the first and third components and a write gap layer located between the first and second pole tip components. The second pole tip is formed with a width that defines a track width of the write head. The third pole tip component is formed with top and bottom surfaces wherein the bottom surface interfaces a top surface of the second pole tip component and has a width equal to the track width and wherein the top surface of the third pole tip has a width greater than the track width.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: March 25, 2008
    Assignee: International Business Machines Corporation
    Inventors: Jyh-Shney (Jerry) Lo, Timothy J. Moran
  • Patent number: 7325294
    Abstract: A method of making electromagnetic wave shielded read and write wires is provided. The method includes forming a bottom insulation layer on a bottom shield layer formed on a substrate. Then, forming electrically conductive wire material into openings in a first forming layer to form first and second read wires and first and second write wires. Forming a top insulation layer on the bottom insulation layer and on the wires. Then, forming a second forming layer on the top insulation layer with first, second, third, fourth and fifth openings down to the top insulation layer. Ion milling portions of the top insulation layer exposed by the openings in the second forming layer down to the bottom shield layer, then removing the second forming layer. Then, forming nonmagnetic electrically conductive middle shield layers in the openings in electrical contact with the bottom shield layer and forming a top shield layer on top of the middle shield layer.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: February 5, 2008
    Assignee: International Business Machines Corporation
    Inventor: Lin Zhou
  • Patent number: 7177120
    Abstract: A magnetic head assembly has a read head that includes a sensor wherein the sensor includes a self-pinned antiparallel (AP) pinned layer structure, a ferromagnetic free layer structure that has a magnetic moment that is free to rotate in response to signal fields and a spacer layer which is located between the free layer and AP pinned layer structures. The self-pinned AP pinned layer structure includes first and second antiparallel (AP) pinned layers, an antiparallel coupling (APC) layer located between and interfacing the first and second AP pinned layers wherein the second AP pinned layer is located between the first AP pinned layer and the spacer layer. The first AP pinned layer is composed of cobalt platinum chromium (CoPtCr).
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: February 13, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: James Mac Freitag, Mustafa Michael Pinarbasi
  • Patent number: 7133264
    Abstract: A current-perpendicular-to-plane (CPP) spin valve (SV) sensor and fabrication method with a contiguous junction type geometry that increases sensor resistance by up to two orders of magnitude over conventional CPP GMR geometry for a particular track read-width. The superior CPP GMR coefficient (?r/R) is implemented at an increased sensor resistance by using two small self-aligned SV stacks disposed with the sense current flowing perpendicular thereto when also flowing parallel to the free layer deposition plane. With the CPP geometry of this invention, thicker conductive spacer layers may be used without unacceptable sense current shunting, so the two self-aligned SV stacks may be completed following the free-layer track-mill step. The two SV stacks may be connected in parallel or back-to-back in series to provide different sense voltages.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: November 7, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Daniele Mauri, Tsann Lin
  • Patent number: 7130153
    Abstract: A magnetic write head assembly has a head surface and a track width at the head surface wherein the head surface forms a first vertical plane and wherein the head assembly includes first and second pole pieces, a write gap located between the first and second pole pieces, the second pole piece having first and second components wherein the first component is located between the write gap and the second component and each of the first and second components has a height into the head which extends from and which is oriented perpendicular to said head surface, the first component having a uniform thickness throughout its height into the head with the height into the head forming a zero throat (ZTH) which lies in a second vertical plane that is parallel to said first vertical plane, the height into the head of the second component being greater than the height into the head of the first component, and each of the first and second components having said track width at the head surface.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: October 31, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yong Shen, Sue S. Zhang
  • Patent number: 7126796
    Abstract: A read head, which has a head surface facing a moving magnetic medium, includes a read sensor that has first and second side top surface portions and a central top surface portion located between the first and second side top surface portions. First and second overlaying lead layers interface the first and second side top surface portions. First and second hard bias and tapered lead layers interface the first and second overlaying lead layers. A central top surface portion of the read sensor has a width that defines a track width of the read sensor. A method of making the read head includes ion-milling a partially oxidized portion of a cap layer and, after depositing the aforementioned first and second hard bias and tapered lead layers, preferentially reactive ion etching (RIE) the overlaying lead layer not covered by the first and second hard bias and tapered lead layers, so as to define the central top surface portion of the read sensor.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: October 24, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Tsann Lin
  • Patent number: 7084467
    Abstract: A spin valve transistor includes an emitter, a collector, a base between the emitter and the collector, a spin valve which includes a free layer structure, a self-pinned antiparallel (AP) pinned layer structure and a nonmagnetic spacer layer between the free layer structure and the AP pinned layer structure wherein the base includes at least the free layer structure.
    Type: Grant
    Filed: July 25, 2003
    Date of Patent: August 1, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal Singh Gill
  • Patent number: 7061728
    Abstract: In a magnetic head a read sensor is located between first and second read gap layers wherein the first read gap layer includes a read gap material layer and first and second refill gap layers. The read gap material layer has first and second depressions which extend laterally from the first and second side walls respectively of the sensor and the first and second refill gap layers are disposed in the first and second depressions and engage a bottom portion of the first side wall and engage a bottom portion of the second side wall respectively. The first read gap layer has first and second portions which extend laterally from the first and second side walls of the sensor and a third portion which engages a bottom surface of the sensor and is located between said first and second portions with each of said first and second portions having a thickness which is greater than a thickness of said third portion.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: June 13, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Mustafa Michael Pinarbasi
  • Patent number: 7054117
    Abstract: Longitudinal biasing of a free layer in a current perpendicular to the planes of the layers (CPP) type of sensor in a read head is implemented by pinning magnetic moments of first and second side portions of the free layer beyond the track width of the read head with first and second insulating antiferromagnetic (AFM) layers which are exchange coupled thereto. The pinning of the magnetic moments of the first and second side portions of the free layer pin and longitudinally bias the central active portion of the free layer within the track width so that the central portion of the free layer is magnetically stable.
    Type: Grant
    Filed: April 17, 2004
    Date of Patent: May 30, 2006
    Assignee: International Business Machines Corporation
    Inventors: Kuok San Ho, Tao Pan
  • Patent number: 7038890
    Abstract: A magnetic read head has a current perpendicular to the planes (CPP) sensor with a top cap layer that is ruthenium (Ru) or rhodium (Rh) or a top cap layer structure which includes a first layer of tantulum (Ta) only, a second layer of ruthenium (Ru), rhodium (Rh) or gold (Au) with the first layer being located between a spacer layer and the second layer.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: May 2, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Mustafa Michael Pinarbasi
  • Patent number: 7031121
    Abstract: A perpendicular recording write head has ferromagnetic first and second pole pieces which are connected at a back gap and an insulation stack with a write coil layer embedded therein is located between the first and second pole pieces and between a head surface of the write head and the back gap. The second pole piece has a pole tip which is located at the head surface and a recessed ferromagnetic write shield layer. A nonmagnetic isolation layer is located between the second pole piece and the write shield layer and at least one ferromagnetic stud is magnetically connected between the first pole piece layer and the write shield layer and is located between the head surface and the insulation stack.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: April 18, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Gautam Khera, Quang Le, Son Van Nguyen, Aron Pentek, Mason Lamar Williams, III
  • Patent number: 7020951
    Abstract: An antiferromagnetic stabilization scheme is employed in a magnetic head for magnetically stabilizing a free layer of a spin valve. This is accomplished by utilizing an antiferromagnetic oxide film below a spin valve sensor in a read region and first and second lead layers in end regions and a ferromagnetic film in each of the lead layers that exchange couples to the antiferromagnetic oxide film in the end regions. The ferromagnetic films are pinned with their magnetic moments oriented parallel to an air bearing surface (ABS) of the magnetic head. The ferromagnetic film magnetostatically couples to the free layer which causes the free layer to be in a single magnetic domain state. Accordingly, when the free layer is subjected to magnetic incursions from a rotating disk in a disk drive, the free layer maintains a stable magnetic condition so that resistance changes of the free layer are not altered by differing magnetic conditions of the free layer.
    Type: Grant
    Filed: November 7, 2003
    Date of Patent: April 4, 2006
    Assignee: International Business Machines
    Inventors: Tsann Lin, Daniele Mauri
  • Patent number: 6988308
    Abstract: Hard biasing of a magnetoresistive sensor or a spin valve sensor in a magnetic read head is initialized by repeatedly applying a magnetic field to the hard biasing at any level of fabrication of the magnetic read head or any combination of levels of fabrication of the read head such as at the wafer level, row bar level, single slider level, head gimbal assembly (HGA) level and/or head stack assembly (HSA) level.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: January 24, 2006
    Assignee: International Business Machines Corporation
    Inventors: Christopher William Bergevin, Carol Inouye Chiu, Robert Yuan-Shih Li, Albert Shou-Chi Su
  • Patent number: 6967825
    Abstract: A GMR sensor has a head surface with an active region and first and second inactive regions along the head surface with the active region being located between the first and second inactive regions, and includes an antiparallel (AP) coupled free layer structure having an active portion and first and second inactive portions located in the active region and the first and second inactive regions respectively. The free layer structure has a free layer, an antiparallel (AP) coupling layer and a ferromagnetic bias layer wherein the AP coupling layer is located between the free layer and the bias layer wherein each of the free layer, the AP coupling layer and the bias layer has an active portion and first and second inactive portions which are located in the active region and the first and second inactive regions respectively.
    Type: Grant
    Filed: April 17, 2003
    Date of Patent: November 22, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal Singh Gill
  • Patent number: 6925702
    Abstract: A horizontal combined head is provided which has both a thin film write and an MR read element located at an air bearing surface (ABS). The read element can be formed with a track width that is independent of the track width of the write element. The MR sensor or the read element is separated from one of the first and second pole pieces of the write element by an insulation layer. Accordingly, the shields for the read element remain more stable after a write operation. In one embodiment of the present invention a single stripe MR sensor is employed while in a second embodiment a dual stripe MR sensor is employed. A method of the invention includes forming the dual MR stripe in a single process step so that the dual MR stripes of the dual MR sensor are near identical for implementing near absolute common mode rejection of noise.
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: August 9, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Mohamad Towfik Krounbi, Mark E. Re
  • Patent number: 6910259
    Abstract: An antiferromagnetic stabilization scheme is employed in a magnetic head for magnetically stabilizing a free layer of a spin valve. This is accomplished by utilizing an antiferromagnetic oxide film below a spin valve sensor in a read region and first and second lead layers in end regions and a ferromagnetic film in each of the lead layers that exchange couples to the antiferromagnetic oxide film in the end regions. The ferromagnetic films are pinned with their magnetic moments oriented parallel to an air bearing surface (ABS) of the magnetic head. The ferromagnetic films magnetostatically couple to the free layer which causes the free layer to be in a single magnetic domain state. Accordingly, when the free layer is subjected to magnetic incursions from a rotating disk in a disk drive, the free layer maintains a stable magnetic condition so that resistance changes of the free layer are not altered by differing magnetic conditions of the free layer.
    Type: Grant
    Filed: November 24, 2000
    Date of Patent: June 28, 2005
    Assignee: International Business Machines Corporation
    Inventors: Tsann Lin, Daniele Mauri
  • Patent number: 6891704
    Abstract: A method of making provides a smooth surface of a pinned or free layer interfacing a barrier layer in a tunnel junction sensor wherein the smooth surface is an oxidized monolayer of the pinned or free layer. After sputter depositing the pinned or free layer the layer is subjected to an oxygen (O2) atmosphere which is extremely low for a very short duration. In a preferred embodiment of the invention a partial thickness of the barrier layer is provided with a smooth surface by the same process after which a remainder thickness of the barrier layer is deposited and the barrier layer is exposed to oxygen (O2) to form an oxide of the deposited metal.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: May 10, 2005
    Assignee: International Business Machines Corporation
    Inventor: Mustafa Pinarbasi
  • Patent number: 6888705
    Abstract: Several embodiments of a sense current perpendicular to the planes of the sensor (CPP) and flux guide type of read head has a gap between first and second shield layers at an air bearing surface (ABS) where the flux guide is located which is less than a gap between the first and second shield layers at a recessed location where the sensor is located. This reduced gap increases the linear bit density capability of the read head. A longitudinal bias stack (LBS) is located in the sensor stack. Several unique methods of construction are described for forming the magnetic head assemblies.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: May 3, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Robert Edward Fontana, Jr., Kuok San Ho, Tao Pan, Ching Hwa Tsang
  • Patent number: 6878240
    Abstract: A sputtering system is provided with a substrate and a sputtering material layer that are located in a sputtering chamber. The sputtering material layer has a sputtering surface where atoms of the material are sputtered and the substrate has a forming surface with a site where atoms of the sputtered material are to be formed. The sputtering material layer has a sputtering center which is located at a center of the atoms to be sputtered and the aforementioned site has a periphery with a forming center at a center of the periphery. The sputtering center is offset from the forming center so that shadowing at outer extremities of photoresist masks near the periphery of the substrate is minimized.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: April 12, 2005
    Assignee: International Business Machines Corporation
    Inventors: Raymond Bus-Kwofie, James Mac Freitag, Lichiao Metin, Mustafa Pinarbasi, Patrick Rush Webb, Serhat Metin
  • Patent number: 6876507
    Abstract: A thin-film write head employing pole pieces formed of an electroplated body-centered cubic (BCC) nickel-iron alloy with a saturation flux density (BS) of 1.9 to 2.3 T (19 to 23 kG) and an acceptable coercivity (HC) of about 80 to about 160 A/m (1-2 Oe). The iron content of the electroplated nickel-iron alloy is from 64% to 81% by weight. The two-layer pole fabrication process holds magnetic anisotropy and coercivity to useable values while improving saturation flux density and optimizing magnetostriction. This is accomplished by first electroplating a BCC nickel-iron layer onto an underlying seed layer and then annealing the two layers to reduce coercivity to less than about 160 amps/meter and raise magnetization to acceptable levels.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: April 5, 2005
    Assignee: International Business Machines Corporation
    Inventors: Mike Ming Yu Chen, Thomas Edward Dinan, Paul Phong Nguyen, Neil Leslie Robertson