Detail Of Magnetic Shielding Patents (Class 360/319)
  • Patent number: 6765767
    Abstract: A read head for use with magnetic recording media having a plurality of magnetic tracks includes a read sensor, first and second magnetic lead shields for improving track resolution, and first and second magnetic shields for improving linear resolution. The read sensor is formed on a side wall of one of the first and second magnetic lead shields using a technique such as ion beam deposition for enhanced film growth rate on the side wall. A magnetic disc drive storage system incorporating the read head and a method of making the read head are also included.
    Type: Grant
    Filed: November 15, 2001
    Date of Patent: July 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Isabel G. Trindade, Michael A. Seigler
  • Patent number: 6765768
    Abstract: A thin-film magnetic head has a lower shield layer and an upper shield layer which are each composed of two layers of a first shield sub-layer and a second shield sub-layer. The second shield sub-layer has a specific resistance higher than that of the first shield sub-layer. Thus, even though the gap length become shorter, the second shield sub-layers and gap layers ensure electrical insulation, and therefore, an electrically insulative thin-film magnetic head can be achieved.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: July 20, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventor: Masamichi Saito
  • Publication number: 20040136118
    Abstract: A magnetic head having a magnetic shield and/or pole layer that is fabricated as a plurality of laminated layers, in which each layer includes a sublayer thickness of Fe(N) and a sublayer thickness of NiFe(N), and where the relative thickness of these two sublayers is graduated. Particularly, the initially deposited laminations include sublayers of NiFe(N) having a thickness that is substantially greater than the thickness of the Fe(N) sublayers, whereas the finally deposited laminations include sublayers having an Fe(N) thickness that is substantially greater than the thickness of the NiFe(N) sublayers.
    Type: Application
    Filed: January 10, 2003
    Publication date: July 15, 2004
    Inventor: Robert Glenn Biskeborn
  • Patent number: 6760198
    Abstract: It is the primary object of the present invention to provide a shield and pole material with reduced magnetostriction while preserving good magnetic characteristics. This material is used in recording heads in tape and disk drives. The material is a repeating sequence of three layers. One layer is FeX(N) where the (N) indicates a nitrogenated film and the additional element, X, is preferentially Ta but can be selected from a group of elements. Another layer is made from a NiFe alloy. The third layer, disposed between the FeX(N) and NiFe layers is tantalum. The sequence of three layers is repeated to build the required thickness for the final material.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: July 6, 2004
    Assignee: International Business Machines Corporation
    Inventor: James Devereaux Jarratt
  • Patent number: 6760199
    Abstract: A magnetic head assembly with an air bearing surface (ABS) layer over a double-shielded magnetoresistive (MR) sensor and a write gap formed between two spaced magnetic pole tips, with an optional write-gap shield disposed so that one magnetic pole tip is disposed between the write-gap shield and the other magnetic pole tip. At least one of the MR element shields is electrically connected to one of the MR signal lead conductors (preferably the one having the most positive potential) and the one magnetic pole tip (and/or the optional write-gap shield) is coupled to the clamped MR element shield with an electrical conductor. For multi-track read/write arrays, the connection between adjacent reader shield and writer pole and/or shield is provided independently for each read/write pair in the array, thereby equalizing the voltage environments to reduce variations in the chemical/mechanical erosion of the read and write head ABS layers.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: July 6, 2004
    Assignee: International Business Machines Corporation
    Inventor: Robert Glenn Biskeborn
  • Publication number: 20040125513
    Abstract: A thin-film magnetic head comprises a magnetoresistive film, a pair of magnetic domain control layers for applying a bias magnetic field to the magnetoresistive film, a pair of electrode layers for supplying a current to the magnetoresistive film, first and second shield layers for shielding the magnetoresistive film, a first insulating layer disposed between the magnetoresistive film and magnetic domain control layer and the first shield layer, and a second insulating layer disposed between the magnetoresistive film and electrode layer and the second shield layer. The shield layers have a distance therebetween shorter at a position where the electrode layer and magnetic domain control layer are laminated than that at a position where the magnetoresistive film is located.
    Type: Application
    Filed: December 5, 2003
    Publication date: July 1, 2004
    Applicant: TDK CORPORATION
    Inventors: Kosuke Tanaka, Koji Shimazawa, Koichi Terunuma
  • Publication number: 20040117976
    Abstract: The method of making a thin-film magnetic head in accordance with the present invention forms a cover layer on an insulating layer about a magnetoresistive film so as to eliminate a protrusion riding on the magnetoresistive film. Then, the protrusion can be eliminated by etching. The part of insulating layer clad with the cover layer is not etched. This can prevent short-circuit from occurring because of thinning the insulating layer.
    Type: Application
    Filed: November 10, 2003
    Publication date: June 24, 2004
    Applicant: TDK CORPORATION
    Inventors: Kazuki Sato, Takeo Kagami
  • Patent number: 6754051
    Abstract: In a spin valve type transducer including two magnetic shield layers, a patterned magnetoresistance element is in direct contact with one of the magnetic shield layers. A permanent magnet layer and an electrode layer are formed on the sides of the patterned magnetoresistance element.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: June 22, 2004
    Assignee: TDK Corporation
    Inventor: Nobuyuki Ishiwata
  • Publication number: 20040114281
    Abstract: A method for forming a planar GMR read-head having a narrow read gap, a narrow track-width and being well insulated from its lower shield. The method requires the formation of a planarized bottom magnetic shield in which concave regions, symmetrically disposed about a track-width region, are filled with a layer of dielectric to provide added insulation. The dielectric filled shield is planarized and an additional planar dielectric layer, a thin planar GMR sensor layer and a planar PMGI layer of uniform thickness is formed on it. A layer of photoresist is deposited on the PMGI layer and a bi-layer lift-off stencil of uniform height above the GMR layer and symmetric overhang regions is formed. The uniformity of the lift-off stencil, which is a result of the planarity of the layers on which it is formed, allows the deposition of conductive lead and biasing layers with controlled overspread.
    Type: Application
    Filed: December 13, 2002
    Publication date: June 17, 2004
    Applicant: Headway Technologies, Inc.
    Inventors: Cherng Chyi Han, Mao-Min Chen, Jiun-Ting Lee
  • Patent number: 6751071
    Abstract: An upper shield layer includes a Ni—Fe alloy underlying film formed by sputtering deposition, and a Ni—Fe alloy plating film formed on the underlying film by electroplating. The Fe composition ratio distribution of the upper shield layer in the thickness direction ranges from 17 to 19% by weight.
    Type: Grant
    Filed: January 16, 2001
    Date of Patent: June 15, 2004
    Assignee: Alps Electric Company Co., Ltd.
    Inventors: Hisayuki Yazawa, Naoki Sakatsume, Yoshihiro Kanada
  • Publication number: 20040100737
    Abstract: A magnetic recording head includes an upper shield layer, a lower shield layer, a magnetoresistive film interposed between the upper shield layer and the lower shield layer, and a pair of leads electrically coupled to the magnetoresistive film, in which a pair of side shield layers constituted by portions of the upper shield layer is formed on both sides of the magnetoresistive film, and a spacing between each side shield layer and the magnetoresistive film is formed to be narrower than twice of a spacing between the upper shield layer and the lower shield layer, thereby a side reading amount can be made smaller than a conventional side reading value determined from the spacing between the upper and lower shield layers and a magnetic spacing between the head and a medium.
    Type: Application
    Filed: June 4, 2003
    Publication date: May 27, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Kazuhiro Nakamoto, Hiroyuki Hoshiya, Chiaki Ishikawa
  • Patent number: 6738233
    Abstract: A read head for perpendicular magnetic recording that reduces side reading. The read head includes a read element and a magnetic shield spaced apart from the read element. The magnetic shield at least partially surrounds the read element at an air-bearing surface of the read element. The ratio of an air-bearing surface area of the magnetic shield to an air-bearing surface area of the read element is from about 1:1 to about 40:1.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: May 18, 2004
    Assignee: Seagate Technology LLC
    Inventors: Sakhrat Khizroev, Dmitri Litvinov, Roy Gustafson, Nisha Shukla
  • Patent number: 6738234
    Abstract: An object of the invention is to provide a thin film magnetic head and a magnetic transducer, which can obtain resistance properties adaptable to ultra-high-density recording. The thin film magnetic head has a stack including a plurality of magnetic layers stacked alternately with a plurality of nonmagnetic layers. The stack is divided into a first region and a second region in a direction of stacking. The first region comprises a projecting portion projecting toward a magnetic medium, an extending portion extending in the direction opposite to the projecting portion, and a pair of wide portions widened in the direction perpendicular to the direction in which the extending portion extends. An end surface of the projecting portion is exposed to the outside and faces the magnetic medium. Thus, the end surface functions as a magnetic field capturing portion for capturing a signal magnetic field of the magnetic medium.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: May 18, 2004
    Assignee: TDK Corporation
    Inventors: Satoru Araki, Koji Shimazawa
  • Patent number: 6735058
    Abstract: A current-perpendicular-to-plane (CPP) read head with an amorphous magnetic bottom shield layer and an amorphous nonmagnetic bottom lead gap layer is disclosed. The amorphous magnetic bottom shield layer and amorphous nonmagnetic bottom lead layer provide a planar surface for the CPP read head deposited thereon to exhibit a low ferromagnetic coupling field and a high giant (or tunneling) magnetoresistance coefficient. The amorphous magnetic bottom shield layer is preferably formed of an Fe-based or Co-based film. The amorphous nonmagnetic bottom lead layer is preferable formed of a W-based or Ni-based film.
    Type: Grant
    Filed: February 4, 2002
    Date of Patent: May 11, 2004
    Assignee: International Business Machines Corporation
    Inventors: Tsann Lin, Daniele Mauri
  • Patent number: 6735059
    Abstract: A magnetoresistive effective type element, comprising: a magnetoresistive effective film; a first shielding film of which one main surface is adjacent to one main surface of said magnetoresistive effective film; a second shielding film of which one main surface is adjacent to the other main surface of said magnetoresistive effective film; and a third shielding film of which one main surface is adjacent to the other main surface of said first shielding film or said second shielding film opposite to said magnetoresistive effective film, wherein said first shielding film and said second shielding film function as current-supplying layers to flow current perpendicular to and through said magnetoresistive effective film, and wherein said first shielding film and said second shielding film are made of at least one selected from the group consisting of NiFe, CoZrTa, FeN, FeAlSi, NiFe alloy, Co-based amorphous material and Fe-based soft magnetic material.
    Type: Grant
    Filed: April 10, 2002
    Date of Patent: May 11, 2004
    Assignee: TDK Corporation
    Inventor: Junichi Sato
  • Patent number: 6731474
    Abstract: Provided are a thin film magnetic head and a method of manufacturing the same, which is capable of high density recording and obtaining stable output. The thin film magnetic head includes an MR film sandwiched in between first and second shield layers. The first shield layer includes an inner layer, a magnetization stabilizing layer, an underlayer, and an outer layer laminated in order from the MR film. The second shield layer includes an inner layer, a magnetization stabilizing layer, an isolating layer, and an outer layer laminated in order from the MR film. The magnetization stabilizing layers are formed of antiferromagnetic material, so as to control the direction of magnetization of the inner layers.
    Type: Grant
    Filed: November 26, 2001
    Date of Patent: May 4, 2004
    Assignee: TDK Corporation
    Inventors: Koichi Terunuma, Ken-ichi Takano, Noriyuki Ito
  • Publication number: 20040075952
    Abstract: A disk drive of a perpendicular magnetic recording system uses a double-layered disk medium including a soft magnetic layer. This disk drive is configured to suppress any adverse effect on a read head element under a magnetic field of a magnetic disturbance applied in a perpendicular direction, which might be caused to occur by being accentuated by a soft magnetic layer.
    Type: Application
    Filed: July 30, 2003
    Publication date: April 22, 2004
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Akihiko Takeo
  • Patent number: 6724569
    Abstract: Embodiments in accordance with the thin film write head of the present invention have a lower pole structure, an upper pole structure, and a multilayer write gap extending from an air bearing surface between the upper and lower pole structures. In preferred embodiments, the write gap comprises at least two of: (a) a first layer covering a lower pole tip portion of the lower pole structure, (b) a second layer covering turns of a semiconductor winding, or (c) a third layer covering a winding insulation stack. In more preferred embodiments, the write gap is formed of the first, the second, and the third write gap layers. An advantage of a write head with a multilayer write gap is that it allows better control of write gap thickness. As such, loss of write gap thickness can be compensated for by deposition of the second write gap layers, or by deposition of the third write gap layer.
    Type: Grant
    Filed: August 23, 2002
    Date of Patent: April 20, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Yingjian Chen, Kyusik Sin, Ronald A. Barr
  • Patent number: 6714374
    Abstract: A magnetoresistive sensor includes a magnetoresistive element and equipment which generates a magnetic field in the magnetoresistive element thereby inducing a biasing magnetic field in the element, where the magnetoresistive element comprises a high electron mobility semiconductor and electrodes which are connected to the semiconductor. If it is an insulator, the equipment, which generates the biasing magnetic field and supplies it to the magnetoresistive element, may contact directly to the magnetoresistive element. If it is a conductor, an insulating separation layer must be set between the equipment and the element. A magnetoresistive element is representatively Corbino disk type or a bar type magnetoresistive element. Another candidate of the magnetoresistive element is an element consisting of a high electron mobility semiconductor, a pair of electrodes which make a current path in the high electron mobility semiconductor, and another pair of electrodes to detect the induced voltage by the current.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: March 30, 2004
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Stuart Solin, Tao Zhou
  • Patent number: 6710982
    Abstract: A read/write head includes a bottom shield and a shared shield. The shared shield includes a first domain and a plurality of closure domains. The read/write head also includes a magnetoresistive sensor deposited adjacent an air bearing surface between the bottom shield and the shared shield. The magnetoresistive sensor includes a magnetoresistor aligned with the first domain. Non-magnetic material separates the magnetoresistive sensor from the bottom shield and the shared shield. The shared shield includes a shaped feature that defines an unambiguous direction of magnetization for the first domain.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: March 23, 2004
    Assignee: Seagate Technology LLC
    Inventors: Anthony M. Mack, Ladislav R. Pust, Christopher J. Rea, Sunita Gangopadhyay, Patrick J. Ryan
  • Patent number: 6704178
    Abstract: A multichannel magnetic head utilizing the magnetoresistive effect comprises a plurality of magnetoresistive effect type reproducing magnetic head elements arrayed between a first and second magnetic shield and electrodes wherein the reproducing magnetic head elements are arrayed in parallel on at least the first magnetic shield and electrode. Electrodes on one side are constructed commonly by the first magnetic shield and led out as a single common terminal decreasing the number of terminals.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: March 9, 2004
    Assignee: Sony Corporation
    Inventors: Eiji Nakashio, Seiji Onoe, Junichi Sugawara
  • Publication number: 20040042126
    Abstract: Disclosed is a CPP structure magnetoresistive head having high output which reduces or prevents deformation near the air bearing surface of a layer constituting a read element portion at the time of air bearing surface processing. In the CPP structure magnetoresistive head, deformation near the air bearing surface which occurs when air bearing surface processing is carried out by mechanical polishing can be reduced by forming deformation prevention layers having a higher shear modulus than a first ferromagnetic layer and a second ferromagnetic layer between a magnetoresistive film and at least one of a lower shield layer and an upper shield layer.
    Type: Application
    Filed: February 21, 2003
    Publication date: March 4, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Katsuro Watanabe, Kikuo Kusukawa, Taku Shintani, Kenichi Meguro
  • Patent number: 6700760
    Abstract: A tunneling magnetoresistive head according to the present invention includes a tunneling magnetoresistive stack having a free layer, a barrier layer, a pinned layer and a pinning layer. The tunneling magnetoresistive stack is configured to operate in a current perpendicular to plane (CPP) mode, wherein a sense current flows substantially perpendicular to a longitudinal plane of the barrier layer. The tunneling magnetoresistive head includes a first shield and a second shield coupled to opposing sides of the tunneling magnetoresistive stack. The first and the second shields act as electrodes to couple the sense current to the tunneling magnetoresistive stack. The first shield has a concave shape and substantially surrounds the free layer. The tunneling magnetoresistive head also includes a spacer layer and a layer of antiferromagnetic material. The spacer layer is formed on the free layer. The layer of antiferromagnetic material is formed on the second spacer layer.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: March 2, 2004
    Assignee: Seagate Technology LLC
    Inventor: Sining Mao
  • Patent number: 6700737
    Abstract: A recording and reproducing separation type magnetic head has a recording head with an upper core and a lower core that writes information on a magnetic disk and a reproducing head with an upper magnetic film and a lower magnetic film, as sealed layers, that reads the information from the magnetic disk. A thickness of the upper part of the upper core is less than a thickness of the tip minute of the upper core. The magnetic head has excellent overwriting performance and achieves high speed transfer.
    Type: Grant
    Filed: August 3, 1999
    Date of Patent: March 2, 2004
    Assignee: Hitachi Global Storage Technologies Japan, Ltd.
    Inventors: Jun Ohno, Takayoshi Ohtsu
  • Patent number: 6697234
    Abstract: A thin-film magnetic head includes a magnetoresistive element, a shielding layer, and an insulating layer disposed between the magnetoresistive element and the shielding layer. The shielding layer is composed of an amorphous material and the surface thereof facing the magnetoresistive element is covered by a crystallization-inhibiting film for inhibiting crystallization of the shielding layer. The crystallization-inhibiting film may have an antioxidizing function for the shielding layer.
    Type: Grant
    Filed: May 10, 2000
    Date of Patent: February 24, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventor: Fumihito Koike
  • Patent number: 6693774
    Abstract: A magnetoresistive sensor which, despite a narrow reproducing shield gap, affords high resolution and high reproducing output because of its structure and is able to minimize the amount of sense current leaking into the shield layer through the gap layer. A magnetic storage apparatus suitable for high-density recording is provided with a magnetic head having said magnetoresistive sensor. The structure is characterized in that at least either of the lower shield layer or upper shield layer is partly or entirely a magnetic layer which is a composite film composed of ferromagnetic metal and oxide, and an insulation protective film is arranged between the electrode film or longitudinal bias film and the magnetic film which is a composite film composed of ferromagnetic metal and oxide.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: February 17, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Katsuro Watanabe, Hiromasa Takahashi, Nobuo Yoshida, Takashi Kawabe, Kazuhiro Nakamoto
  • Patent number: 6686068
    Abstract: A CPP magnetoresistive sensor with a spacer layer made of a heterogeneous material, which is composed of conductive grains within a highly resistive matrix, has a high resistance. The conductive grains are typically made of a conductive element or alloy that can operate as a GMR spacer material. The highly resistive matrix is typically made of a highly resistive or insulating element, alloy or compound that will hinder the flow of electrons. The sensing electrical current is passed through the conductive grains, which are typically made of the same material as GMR spacers, so the GMR is maintained even though the overall resistance is increased.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: February 3, 2004
    Assignee: International Business Machines Corporation
    Inventors: Matthew Joseph Carey, Jeffrey Robinson Childress, Bruce Alvin Gurney
  • Publication number: 20040017640
    Abstract: A magneto-resistive read head having a “parasitic shield” provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.
    Type: Application
    Filed: February 2, 2001
    Publication date: January 29, 2004
    Inventors: Timothy Scott Hughbanks, Neil Leslie Robertson, Steven Howard Voldman, Albert John Wallash
  • Patent number: 6683760
    Abstract: A thin film magnetic head that is ready for positioning of the elevation of the MR layer and most suitable for high density recording to be used for the helical scan type magnetic recording and reproducing apparatus, comprising a lower shield layer formed on a substrate, a lower gap layer formed on the upper shield layer, a magnetoresistive layer formed on the lower shield layer via the lower gap layer, an upper gap layer formed on the magnetoresistive layer, and an upper shield layer formed on the magnetoresistive layer via the upper gap layer, besides providing a convex portion on the principal face of the upper shield layer.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: January 27, 2004
    Assignee: Alps Electric Co., Ltd.
    Inventor: Katsuya Kikuiri
  • Publication number: 20040012894
    Abstract: A magnetic head includes a substrate and a data transducer positioned upon the substrate. The data transducer includes a reader comprised of a top shield and a bottom shield characterized by at least one of the shields including a layer for compensating a thermally-caused expansion of the reader.
    Type: Application
    Filed: February 27, 2003
    Publication date: January 22, 2004
    Applicant: Seagate Technology LLC
    Inventors: Ladislav Rudolf Pust, Mark Thomas Kief, Ibro Tabakovic, James F. Dolejsi, Vee Sochivy Kong
  • Patent number: 6680832
    Abstract: A current-perpendicular-to-the-plane (CPP) magnetoresistive sensor or read head has a magnetic shield geometry that covers the side walls of the sensor structure to prevent side reading caused by magnetic flux entering from adjacent data tracks. The shield geometry includes a bottom shield with a substantially planar surface and a specially shaped top shield. The top shield has substantially vertical portions generally parallel to the side walls of the sensor structure, a horizontal top portion over the trackwidth region of the sensor, and horizontal side portions formed over the portions of the bottom shield on either side of the sensor structure. The insulating gap material that separates the bottom and top shields is in contact with the horizontal portions of the bottom shield and the side walls of the sensor structure.
    Type: Grant
    Filed: May 11, 2001
    Date of Patent: January 20, 2004
    Assignee: International Business Machines Corporation
    Inventors: Robert E. Fontana, Jr., Kuok San Ho, Jordan A. Katine, Jeffrey S. Lille, Ching H. Tsang
  • Patent number: 6680829
    Abstract: A magnetoresistive (MR) sensor for use in a magnetic storage system including a magnetic storage media having multiple concentric microtracks with information stored thereon. The MR sensor includes a plurality of generally parallel layers that form an MR stack. The MR sensor also includes a top shield and a bottom shield that are spaced apart on opposite sides of the MR stack in a longitudinal direction. The Mr sensor further includes a first and a second side shield spaced apart on opposite sides of the MR stack in a transverse direction. The top shield, bottom shield, first side shield and second side shield substantially surround the MR stack.
    Type: Grant
    Filed: August 20, 2001
    Date of Patent: January 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Lujun Chen, James Giusti, Juan Jose Fernandez-de-Castro, Jian Chen, Sining Mao
  • Patent number: 6678126
    Abstract: The part of an MR element 25 which lies close to a medium-facing surface 10a overlaps that part of a flux-guiding element 24 which lies remote from the medium-facing surface 10a, with a second gap film 23b interposed between the elements 24 and 25. Further, the MR element 25 overlaps the flux-guiding element 24 for a distance that falls within a range of 15 to 25% of the length of the MR height of the element 25 as measured in a direction perpendicular to the medium-facing surface 10a.
    Type: Grant
    Filed: October 19, 2001
    Date of Patent: January 13, 2004
    Assignee: Sony Corporation
    Inventors: Toru Katakura, Takuji Matsuo, Eiji Nakashio, Junichi Sugawara, Seiji Onoe
  • Patent number: 6673633
    Abstract: A thin-film magnetic head includes a top pole layer that defines a write track width. The top pole layer is formed as follows. A high saturation flux density material such as FeN or FeCo is sputtered to form a film to be patterned. A magnetic layer having a specific pattern is formed on this film to be patterned. Using the magnetic layer as a mask, the film is etched through reactive ion etching. The film is thereby patterned and a pole portion layer is formed. Next, cross-sectional surfaces of the pole portion layer obtained through the reactive ion etching are slightly etched to remove deposits.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: January 6, 2004
    Assignee: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Patent number: 6665152
    Abstract: Magnetic heads capable of recording and reading with high sensitivity and resolution are provided by minimizing the outflow of magnetic fluxes from a flux guide to magnetic shields while using a flux guide structure for an MR element. In the magnetic head, magnetic shields exposed on a surface opposite a magnetic recording medium (air bearing surface) and a flux guide exposed between the magnetic heads via a non-magnetic layer are provided, and magnetic fluxes are guided by the flux guide to a magnetoresistive (MR) element formed in a position not exposed on the air bearing surface. The height of the magnetic shields in a direction perpendicular to the air bearing surface is less than the distance from the air bearing surface to the MR element, and the lengthwise direction of the magnetic shields is in parallel to the air bearing surface in the vicinity of the position in which the flux guide is formed.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: December 16, 2003
    Assignee: Hitachi, Ltd.
    Inventor: Hiroaki Nemoto
  • Patent number: 6657824
    Abstract: It is assumed that W1 is the width for an end face of the lower magnetic shield thin film 4 which is exposed outward from the tape sliding surface 1a. It is also assumed that W2 corresponds to the sum of the width for an end face of the MR element 7 which is exposed outward from the tape sliding surface 1a and widths for end faces of a pair of ferromagnetic films 9 and 10 which are exposed outward therefrom. The width W1 is determined to be smaller than W2. When the MR head 1 is mounted on the head support plate 30 or the rotary drum 42, it is possible to use as a marker the lower magnetic shield thin film 4's end face exposed from the tape sliding surface.
    Type: Grant
    Filed: October 12, 2000
    Date of Patent: December 2, 2003
    Assignee: Sony Corporation
    Inventor: Kazunori Onuma
  • Patent number: 6654209
    Abstract: A magnetic recording head includes a current perpendicular to the plane read head having a read sensor and a low resistance lead structure. The lead structure includes a layer of conductive material that forms at least a portion of the lead structure such that the layer of conductive material has a lower resistivity than a resistivity of the remainder of the lead structure. The layer of conductive material with lower resistivity decreases the overall resistance of the lead structure.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: November 25, 2003
    Assignee: Seagate Technology LLC
    Inventors: Michael Allen Seigler, Petrus Antonius Van der Heijden, Gregory John Parker, Billy Wayne Crue
  • Publication number: 20030214759
    Abstract: A magnetic reading head is provided. The magnetic reading head reads information recorded on a recording medium having a soft underlayer and a magnetic layer stacked on the soft underlayer, and includes a magneto-resistive element and a pair of shield layers. The magneto-resistive element is positioned over the magnetic layer, keeping a predetermined distance G from the soft underlayer. The pair of shield layers are arranged parallel to the magneto-resistive element, keeping predetermined distances from both sides of the magneto-resistive element. Here, the shield layers have widths less than double of the predetermined distance G. In this structure, by properly adjusting the widths of the shield layers, magnetic fields formed by the magnetization of the recording medium under the shield layers do not affect the magnetoresistive element. As a result, sensitivity of the magnetic reading head can be improved.
    Type: Application
    Filed: February 5, 2003
    Publication date: November 20, 2003
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Yong-Su Kim
  • Patent number: 6650510
    Abstract: Provided is a magnetic head including a bottom pole, a top pole spaced a predetermined distance apart from the bottom pole, an inductive write coil for forming a magnetic field at the bottom and top poles, and a magnetic shield layer positioned over the top pole.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: November 18, 2003
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-su Kim, No-yeol Park
  • Publication number: 20030206379
    Abstract: A current-perpendicular-to-plane (CPP) read head with an amorphous magnetic bottom shield layer and an amorphous nonmagnetic bottom lead gap layer is disclosed. The amorphous magnetic bottom shield layer and amorphous nonmagnetic bottom lead layer provide a planar surface for the CPP read head deposited thereon to exhibit a low ferromagnetic coupling field and a high giant (or tunneling) magnetoresistance coefficient. The amorphous magnetic bottom shield layer is preferably formed of an Fe-based or Co-based film. The amorphous nonmagnetic bottom lead layer is preferable formed of a W-based or Ni-based film.
    Type: Application
    Filed: February 4, 2002
    Publication date: November 6, 2003
    Inventors: Tsann Lin, Daniele Mauri
  • Patent number: 6643105
    Abstract: A magnetic head include a pair of magnetic shield layers, a pair of gap layers formed between the pair of magnetic shield layers, a magnetoresistive layer arranged between the pair of gap layers, and a pair of electrodes electrically connected to the magnetoresistive layer. At least one of the pair of magnetic shield layers is formed as a discontinuous multi-layer or as a mixed layer.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: November 4, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Nakamoto, Hiroyuki Hoshiya, Takashi Kawabe, Hiromasa Takahashi, Hisashi Kimura, Katsuro Watanabe, Chiaki Ishikawa, Kaori Totsuka
  • Patent number: 6643104
    Abstract: An MR thin-film magnetic head includes a lower shield layer, an upper shield layer, a MR multilayer sandwiched between the lower shield layer and the upper shield layer, the MR multilayer being electrically connected with the lower shield layer and the upper shield layer, a current flowing through the MR multilayer in a direction perpendicular to surfaces of layers, and a lead conductor having one end electrically connected to the upper shield layer and the other end connected to a terminal electrode. The lead conductor is patterned such that an area of said lead conductor located above said lower shield layer becomes small.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: November 4, 2003
    Assignee: TDK Corporation
    Inventor: Koji Shimazawa
  • Publication number: 20030197981
    Abstract: In a spin value type transducer including two magnetic shield layers, a patterned magnetoresistance element is in direct contact with one of the magnetic shield layers. A permanent magnet layer and an electrode layer are formed on the sides of the patterned magnetoresistance element.
    Type: Application
    Filed: May 28, 2003
    Publication date: October 23, 2003
    Applicant: TDK Corporation
    Inventor: Nobuyuki Ishiwata
  • Patent number: 6631550
    Abstract: A method of manufacturing a thin-film magnetic head includes the steps of: forming a first shield layer and a first portion of a second shield layer to be placed in one plane and insulated from each other; forming at least part of a thin-film coil on the first portion of the second shield layer such that the coil is insulated from the first portion; forming a first insulating layer on the first shield layer; forming a magnetoresistive element on the first insulating layer; forming a second insulating layer on the magnetoresistive element; forming a second portion of the second shield layer on the second insulating layer; forming a gap layer on the second portion of the second shield layer; and forming a second magnetic layer on the gap layer.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: October 14, 2003
    Assignee: TDK Corporation
    Inventor: Yoshitaka Sasaki
  • Patent number: 6633459
    Abstract: The invention is a magnetoresistive recording head including the reader portion that has a top and bottom shield, a first auxiliary electrical connection, a second auxiliary electrical connection, a first auxiliary electrical contact, and a second auxiliary electrical contact, where the first auxiliary electrical connection electrically connects the first auxiliary electrical contact to the top shield, and where the second auxiliary electrical connection electrically connects the second auxiliary electrical contact to the bottom shield.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: October 14, 2003
    Assignee: Seagate Technology LLC
    Inventors: Kevin Richard Heim, Clifton H. Chang, Peter Thomas Weyandt, Patrick Joseph Ryan
  • Patent number: 6628484
    Abstract: A magnetoresistive (MR) read head is disclosed including a shield layer with a recessed portion and a protruding portion defined by the recessed portion. Also included is an MR sensor located in vertical alignment with the protruding portion of the shield layer. Further provided is at least one gap layer situated above and below the MR sensor. At least one of such gap layers is positioned in the recessed portion of the shield layer. By this design, a combined thickness of the gap layers is thinner adjacent to the MR sensor and the protruding portion of the shield layer, while being thicker adjacent to the recessed portion of the shield layer. As such, optimum insulation is provided while maintaining planar gap layer surfaces to avoid the detrimental ramifications of reflective notching and the swing curve effect.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: September 30, 2003
    Assignee: International Business Machines Corporation
    Inventor: Douglas Werner
  • Publication number: 20030179506
    Abstract: The object of the present invention is to provide a magnetoresistive magnetic head having good, stable playback characteristics. In an MR head wherein an MR element is interposed between a lower shield layer and an upper shield layer, separated by non-magnetic layers. The lower shield layer and the upper shield layer are formed from a material having high permeability and high resistivity. Since the magnetic shield layers are formed from materials having high permeability and high resistivity, even if friction causes dragging of the head surface, there is effectively no short circuit between the magnetic shield layer and the magnetic element.
    Type: Application
    Filed: October 30, 2002
    Publication date: September 25, 2003
    Applicant: Mitsumi Electric Co., Ltd.
    Inventor: Yasuhiko Shinjo
  • Publication number: 20030174446
    Abstract: A magnetic sensing element of a current-perpendicular-to-plane (CPP) type that minimizes an increase in effective read track width and prevents side reading is provided. The magnetic sensing element includes a composite film, an upper shield layer, a lower shield layer, and side shield layers. The side shield layers are disposed at the two sides of the composite film in the track width direction between the lower shield layer and the upper shield layer.
    Type: Application
    Filed: March 10, 2003
    Publication date: September 18, 2003
    Applicant: Alps Electric Co., Ltd.
    Inventor: Naoya Hasegawa
  • Patent number: 6618227
    Abstract: A magnetic recording apparatus has a two-layered medium of a soft magnetic backing layer and a perpendicular recording layer, and a perpendicular recording head having a recording section including a main magnetic pole, an auxiliary magnetic pole and an exciting coil, and a reproducing section including a reproducing element sandwiched between a pair of reproducing shields, the reproducing section and the recording section being formed separately from each other. The auxiliary magnetic pole is recessed from the air-bearing surface of the main magnetic pole, and the distance between the auxiliary magnetic pole and the reproducing shield positioned adjacent to the auxiliary magnetic pole is set to permit a magnetic field generated under the auxiliary magnetic pole to be larger than a magnetic field under the shield.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: September 9, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Yano, Akihiko Takeo
  • Patent number: 6614629
    Abstract: The present invention provides a thin film magnetic head which is prevented from producing a great step in an upper shield layer and which can decrease the probability of a short circuit between the upper shield layer or lower shield layer and a spin-valve thin film magnetic element. The thin film magnetic head includes a spin-valve thin film magnetic element including a lamination of a free magnetic layer, a nonmagnetic conductive layer, a pinned magnetic layer, and an antiferromagnetic layer, a pair of conductive layers for supplying a sensing current to the free magnetic layer, and a pair of insulating bias layers for orienting the magnetization direction of the free magnetic layer; and a pair of shield layers laminated on both sides of the spin-valve thin film magnetic element in the direction of the thickness thereof.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: September 2, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventor: Yoshihiko Kakihara