Detail Of Sense Conductor Patents (Class 360/322)
  • Publication number: 20030223158
    Abstract: A reproducing head of a thin-film magnetic head incorporates an MR element, a pair of bias field applying layers located to be adjacent to side portions of the MR element, and a pair of electrode layers that are located on the bias field applying layers and overlap the MR element. The electrode layers each have a first layer, a second layer, and a third layer. The first layer is laid over part of the top surface of the MR element via a protection layer, the second layer overlaps the first layer, and the third layer is located on the second layer. The second layer is thinner than the third layer. In the method of manufacturing the reproducing head, after the protection layer is formed on an element-to-be film to make the MR element, a first electrode-to-be film to make the first layers is formed continuously without interposing a step of exposing the protection layer to the air.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 4, 2003
    Applicants: Headway Technologies, Inc., SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshitaka Sasaki, Takehiro Kamigama
  • Patent number: 6657826
    Abstract: A magnetoresisive device comprises: an MR element having two surfaces that face toward opposite directions and two side portions that face toward opposite directions; two bias field applying layers that are located adjacent to the side portions of the MR element and apply a longitudinal bias magnetic field to the MR element; and two electrode layers that are located adjacent to one of the surfaces of each of the bias field applying layers and feed a sense current to the MR element. The electrode layers overlap the one of the surfaces of the MR element. The magnetoresistive device further comprises two nonconductive layers that are located between the one of the surfaces of the MR element and the two electrode layers and located in two regions that include ends of the MR element near the side portions thereof, the two regions being parts of the region in which the electrode layers face toward the one of the surfaces of the MR element.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: December 2, 2003
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Koichi Terunuma
  • 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: 20030214760
    Abstract: A reproducing head of a thin-film magnetic head incorporates an MR element, a pair of bias field applying layers located to be adjacent to the side portions of the MR element, and a pair of electrode layers that are located on the bias field applying layers and overlap the MR element. The electrode layers each have a first layer that is laid over part of the top surface of the MR element via a protection layer, and a second layer that overlaps the first layer. In the method of manufacturing the reproducing head, after forming the protection layer on an element-to-be film to make the MR element, a first electrode-to-be film to make the first layers is formed continuously without interposing a step of exposing the protection layer to the air.
    Type: Application
    Filed: May 17, 2002
    Publication date: November 20, 2003
    Applicants: Headway Technologies, Inc., SAE Magnetics (H.K. ) Ltd.
    Inventors: Yoshitaka Sasaki, Takehiro Kamigama
  • Publication number: 20030214761
    Abstract: A lead overlay magnetic sensor for use in a disk drive is provided having a protective cap layer disposed between the electrical leads and the sensor. The protective cap layer is preferably formed from ruthenium, rhodium, or other suitable material. The sensors thus formed have low resistance between the electrical leads and the sensor and also have well defined magnetic trackwidths.
    Type: Application
    Filed: May 16, 2002
    Publication date: November 20, 2003
    Inventors: James Mac Freitag, Mustafa Pinarbasi, Patrick Rush Webb
  • 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: 6643107
    Abstract: The invention provides a spin valve thin film element in which output characteristics and the stability of reproduced waveforms are improved, asymmetry is decreased, and the occurrence of side reading is prevented. The spin valve thin film element includes a lamination having an antiferromagnetic layer, a first pinned magnetic layer, a nonmagnetic intermediate layer, a second pinned magnetic layer, a nonmagnetic conductive layer, a free magnetic layer, and a backed layer composed of a nonmagnetic conductive material, which are laminated on a substrate. Hard bias layers are formed on both sides of the lamination, and orient the magnetization direction of the free magnetic layer in the direction crossing the magnetization direction of the second pinned magnetic layer. Electrode layers are formed on the hard bias layers to supply a sensing current J to the lamination. The electrode layers are formed to extend to the surface of the lamination toward the central portion from both sides of the lamination.
    Type: Grant
    Filed: October 4, 2000
    Date of Patent: November 4, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventors: Naoya Hasegawa, Kiyoshi Sato, Kenji Honda
  • Publication number: 20030189798
    Abstract: The GMR read head includes a GMR read sensor and a longitudinal bias (LB) stack in a read region, and the GMR read sensor, the LB stack and a first conductor layer in two overlay regions. In its fabrication process, the GMR read sensor, the LB stack and the first conductor layer are sequentially deposited on a bottom gap layer. A monolayer photoresist is deposited, exposed and developed in order to open a read trench region for the definition of a read width, and RIE is then applied to remove the first conductor layer in the read trench region. After liftoff of the monolayer photoresist, bilayer photoresists are deposited, exposed and developed in order to mask the read and overlay regions, and a second conductor layer is deposited in two unmasked side regions. As a result, side reading is eliminated and a read width is sharply defined by RE.
    Type: Application
    Filed: April 5, 2002
    Publication date: October 9, 2003
    Inventors: Tsann Lin, Daniele Mauri
  • Publication number: 20030189799
    Abstract: A magnetoresistive reproducing head is manufactured by forming a magnetoresistive film and a lead layer continuously, then etching only the lead layer by using a first layer photo-resist pattern, forming a second layer photo-resistive pattern while leaving the first layer photo-resist pattern, etching the magnetoresistive film and then forming a domain control film and an outer lead layer, thereby enabling to avoid the effect at all on the positional relation between the lead layer and domain control film, whereby a head in which the riding amount of the lead layer on the magnetoresistive film is in right-to-left symmetry and the sensitivity profile is in right-to-left symmetry can be manufactured at a good yield.
    Type: Application
    Filed: August 16, 2002
    Publication date: October 9, 2003
    Inventors: Yasunobu Yanagisawa, Akira Morinaga, Masatoshi Arasawa, Shuichi Kojima, Makoto Morijiri
  • Publication number: 20030179508
    Abstract: A magnetic head is made of a shield layer having first and second recesses defined in first and second end regions which surround a central region. Bias and lead layers are formed in the first and the second recesses, and a read sensor is formed in the central region. Advantageously, edges of the bias and lead layers are formed below edges of the read sensor to thereby define a magnetic track width of the read sensor. Also, the sensor profile is substantially flat so that a gap layer over the read sensor can provide for adequate insulation.
    Type: Application
    Filed: March 22, 2002
    Publication date: September 25, 2003
    Inventor: Hugo Alberto Emilio Santini
  • Publication number: 20030179509
    Abstract: A spin valve sensor has an antiparallel (AP) pinned layer structure which has ferromagnetic first and second AP pinned layers that are separated by an antiparallel coupling layer. The first and second AP pinned layers are self-pinned antiparallel with respect to one another without the assistance of an antiferromagnetic (AFM) pinning layer. First and second hard bias layers interface first and second side surfaces of the spin valve sensor and the sensor has a central portion that extends between the first and second hard bias layers. First and second lead layers overlay the first and second hard bias layers and overlay first and second end portions of the central portion so that a distance between the first and second lead layers defines a track width that is less than a distance between the first and second hard bias layers.
    Type: Application
    Filed: March 21, 2002
    Publication date: September 25, 2003
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: Mustafa Pinarbasi
  • Publication number: 20030179507
    Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer structure which is self-pinned without the assistance of an antiferromagnetic (AFM) pinning layer. A free layer of the spin valve sensor has first and second wing portions which extend laterally beyond a track width of the spin valve sensor and are exchange coupled to first and second AFM pinning layers. Magnetic moments of the wing portions of the free layer are pinned parallel to the ABS and parallel to major planes of the layers of the sensor for magnetically stabilizing the central portion of the free layer which is located within the track width. The spin valve sensor has a central portion that extends between the first and second AFM layers. First and second lead layers overlay the first and second AFM layers and further overlay first and second portions of the central portion so that a distance between the first and second lead layers defines a track width that is less than a distance between the first and second AFM layers.
    Type: Application
    Filed: March 21, 2002
    Publication date: September 25, 2003
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: James Mac Freitag, Mustafa Pinarbasi, Patrick Rush Webb
  • Publication number: 20030165034
    Abstract: Disclosed is a system and a method for reducing high frequency interference pickup by the read element of the magneto-recording head. The reduction is achieved by reducing the parisitic capacitance between certain elements of the magnetic head. In one embodiment, the areas of the pads and leads, including the areas of the leads over the S1 and the areas of the sensor leads, are reduced. A second implementation involves increasing the separation between the pads and leads and the substrate material. Copper studs or vias may be used to connect the contact pads and the underlying layers. A third implementation includes using a low dielectric constant material as a spacer layer between conductors (leads, pads, magnetic shields) and the substrate.
    Type: Application
    Filed: March 1, 2002
    Publication date: September 4, 2003
    Inventors: Vladimir Nikitin, Michael Paul Salo, Samuel W. Yuan, Robert Langland Smith, Mark Allen Burleson
  • Patent number: 6612018
    Abstract: A method of making a read head includes forming a spin valve sensor with an antiparallel pinned layer that has an AP coupling film located between and interfacing first and second ferromagnetic films wherein the first and second ferromagnetic films are composed of Co90Fe10. Another aspect forms the spin valve sensor with a free layer which has a nickel iron (NiFe) film located between and interfacing third and fourth ferromagnetic films composed of Co90Fe10. Still another aspect forms the spin valve sensor with a sense current field (SCF) pinned layer that is spaced from the free layer and is pinned by sense current fields from other conductive layers of the spin valve sensor.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: September 2, 2003
    Assignee: International Business Machines Corporation
    Inventor: Hardayal Singh Gill
  • Publication number: 20030156359
    Abstract: A thin-film electrode layer having a superior electromigration resistance is disclosed. The thin-film electrode layer includes a first base layer composed of &bgr;-Ta, a main conductive layer composed of Au, and a protective layer. The protective layer is a composite of a Cr sublayer and an &agr;-Ta sublayer. A thin-film magnetic head having the thin-film electrode layers and a method for forming electrodes in the thin-film magnetic head are also disclosed.
    Type: Application
    Filed: February 18, 2003
    Publication date: August 21, 2003
    Inventors: Akira Takahashi, Jun Takahashi, Yuko Kawasaki, Kenji Honda, Naohiro Ishibashi, Eiji Umetsu
  • Patent number: 6587315
    Abstract: A magnetoresistive-effect device includes a multilayer film, hard bias layers arranged on both sides of the multilayer film, and electrode layers respectively deposited on the hard bias layers. The electrode layers are formed, extending over the multilayer film. Under the influence of the hard bias layers arranged on both sides of the multilayer, the multilayer film, forming the magnetoresistive-effect device, has, on the end portions thereof, insensitive regions which exhibit no substantial magnetoresistive effect. The insensitive region merely increases a direct current resistance. By extending the electrode layers over the insensitive regions of the multilayer film, a sense current is effectively flown from the electrode layer into the multilayer film. With a junction area between the electrode layer and the multilayer film increased, the direct current resistance is reduced, while the reproduction characteristics of the device are thus improved.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: July 1, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventors: Daigo Aoki, Naoya Hasegawa, Kenji Honda, Kiyoshi Sato, Yoshihiko Kakihara
  • Publication number: 20030107850
    Abstract: A magnetoresistive-effect device includes a multilayer film, hard bias layers arranged on both sides of the multilayer film, and electrode layers respectively deposited on the hard bias layers. The electrode layers are formed, extending over the multilayer film. Under the influence of the hard bias layers arranged on both sides of the multilayer, the multilayer film, forming the magnetoresistive-effect device, has, on the end portions thereof, insensitive regions which exhibit no substantial magnetoresistive effect. The insensitive region merely increases a direct current resistance. By extending the electrode layers over the insensitive regions of the multilayer film, a sense current is effectively flown from the electrode layer into the multilayer film. With a junction area between the electrode layer and the multilayer film increased, the direct current resistance is reduced, while the reproduction characteristics of the device are thus improved.
    Type: Application
    Filed: January 6, 2003
    Publication date: June 12, 2003
    Applicant: Alps Electric Co., Ltd.
    Inventors: Daigo Aoki, Naoya Hasegawa, Kenji Honda, Yoshihiko Kakihara
  • Publication number: 20030103298
    Abstract: A magnetoresistive-effect device includes a multilayer film, hard bias layers arranged on both sides of the multilayer film, and electrode layers respectively deposited on the hard bias layers. The electrode layers are formed, extending over the multilayer film. Under the influence of the hard bias layers arranged on both sides of the multilayer, the multilayer film, forming the magnetoresistive-effect device, has, on the end portions thereof, insensitive regions which exhibit no substantial magnetoresistive effect. The insensitive region merely increases a direct current resistance. By extending the electrode layers over the insensitive regions of the multilayer film, a sense current is effectively flown from the electrode layer into the multilayer film. With a junction area between the electrode layer and the multilayer film increased, the direct current resistance is reduced, while the reproduction characteristics of the device are thus improved.
    Type: Application
    Filed: January 6, 2003
    Publication date: June 5, 2003
    Applicant: Alps Electric Co., Ltd.
    Inventors: Kenji Honda, Kiyoshi Sato, Yoshihiko Kakihara
  • Patent number: 6570743
    Abstract: The present invention extends the high resistance lead layers of a read head straight back into the head from each of the first and second edges of the read sensor. This lessens the length of each of the high resistance lead layers so that they do not have to be made thicker to satisfy resistance requirements. Accordingly, a lateral width of each high resistance lead portion along the ABS and a thickness thereof are chosen so as to minimize the thickness while yet satisfying the resistance requirements. Further, a method of making the first and second lead layers is provided that minimizes the thickness of the high resistance lead layers. Instead of constructing the high resistance lead layers first, the present method constructs the high resistance lead layers after defining a stripe height of the read sensor so that the lateral expanse of the high resistance lead layers is not altered by ion milling, which ion milling increases the resistance of the high resistance lead layers.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: May 27, 2003
    Assignee: International Business Machines Corporation
    Inventors: Glen Adam Garfunkel, Wen-Chien (David) Hsiao, Edward Hinpong Lee, Douglas Johnson Werner
  • Patent number: 6570745
    Abstract: An improved magnetic head for a hard disk drive including a lead overlaid read head component in which the magnetic fields of the passive region of the free magnetic layer regions are pinned. In one embodiment a thin film layer composed of a magnetic material is deposited on top of the free layer of the GMR head in the passive region beneath the overlaid electrical leads. In an alternative embodiment the passive region of the free layer is anti-parallel coupled.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: May 27, 2003
    Assignee: International Business Machines Corporation
    Inventor: Hardayal Singh Gill
  • Publication number: 20030095362
    Abstract: A magnetoresistive-effect device includes a multilayer film, hard bias layers arranged on both sides of the multilayer film, and electrode layers respectively deposited on the hard bias layers. The electrode layers are formed, extending over the multilayer film. Under the influence of the hard bias layers arranged on both sides of the multilayer, the multilayer film, forming the magnetoresistive-effect device, has, on the end portions thereof, insensitive regions which exhibit no substantial magnetoresistive effect. The insensitive region merely increases a direct current resistance. By extending the electrode layers over the insensitive regions of the multilayer film, a sense current is effectively flown from the electrode layer into the multilayer film. With a junction area between the electrode layer and the multilayer film increased, the direct current resistance is reduced, while the reproduction characteristics of the device are thus improved.
    Type: Application
    Filed: January 6, 2003
    Publication date: May 22, 2003
    Applicant: Alps Electric Co., Ltd.
    Inventors: Daigo Aoki, Naoya Hasegawa, Kenji Honda, Yoshihiko Kakihara
  • Patent number: 6542340
    Abstract: In a magnetoresistance element including a lower electrode layer which is formed directly on a lower shield layer or on another layer which is formed on the lower shield layer or so as to serve also as the lower shield layer; a magnetoresistance effect layer which is formed on part of the upper surface of the lower electrode layer; and an upper electrode layer which is formed above the lower electrode layer so that part of its lower surface will at least be in contact with the upper surface of the magnetoresistance effect layer, the upper electrode layer is formed so that the upper electrode layer seen in a plan view will avoid the edge of the lower electrode layer except at the ABS (Air Bearing Surface) of the magnetoresistance element.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: April 1, 2003
    Assignee: NEC Corporation
    Inventor: Kazuhiko Hayashi
  • Publication number: 20030058585
    Abstract: A thin film magnetic head has a reading element including a magnetoresistive effective film, a pair of magnetic domain-controlling films and a pair of electrode films. The magnetic domain-controlling films are provided both sides of the magnetoresistive effective film in a track width direction, respectively, so that the depth of the magnetic domain-controlling films is set equal to the depth of the magnetoresistive effective film in a depth direction perpendicular to the track width direction. The electrode films are provided on the magnetic domain-controlling films so as to have elongated portions, respectively, beyond a region where the depth of the magnetic domain-controlling films is set equal to the depth of the magnetoresistive effective film.
    Type: Application
    Filed: July 10, 2002
    Publication date: March 27, 2003
    Applicant: TDK Corporation
    Inventor: Shigeru Shoji
  • Patent number: 6538856
    Abstract: A first lead is connected to an edge of a free layer of a spin valve sensor for conducting a sense current parallel to the planes of its film surfaces after which the sense current is conducted perpendicular to the planes of the film surfaces of the remainder of the layers of the spin valve sensor to a second lead layer which may be a first shield layer of the read head. The conduction of the sense current parallel to the film surfaces of the free layer provides the spin valve sensor with sufficient resistance so as to enable processing circuitry to efficiently produce playback signals.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: March 25, 2003
    Assignee: International Business Machines Corporation
    Inventor: Hardayal Singh Gill
  • Publication number: 20030053265
    Abstract: A magnetoresistive effective film responds commensurate with an external magnetic field. Magnetic domain-controlling films apply a perpendicular biasing magnetic field to the magnetoresistive effective film. The forefronts of first electrode films constituting a pair of electrode films are overlaid on the magnetoresistive effective film, and the forefront surfaces of the first electrode films are risen at an inner angle of &thgr;1. Second electrode films are overlaid on the first electrode films, and the forefront surfaces of the second electrode films are risen at an inner angle of &thgr;2 smaller than the inner angle &thgr;1.
    Type: Application
    Filed: July 10, 2002
    Publication date: March 20, 2003
    Applicant: TDK CORPORATION
    Inventors: Koichi Terunuma, Koji Shimazawa, Akifumi Kamijima
  • Patent number: 6532647
    Abstract: A manufacturing method of a composite type thin-film magnetic head with a reading head element and an inductive writing head element, includes a step of forming the reading head element and its lead conductor layers on a first insulation layer, a step of forming a second insulation layer to cover the reading head element and the lead conductor layers, a step of forming a second shield layer on the second insulation layer, a step of forming a third insulation layer, and a step of forming via holes and a back gap hole. The via holes and back gap hole forming step is executed by reactive ion etching (RIE) for simultaneously removing the second insulation layer and the third insulation layer located at the via holes and the third insulation layer located at the back gap hole.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: March 18, 2003
    Assignee: TDK Corporation
    Inventors: Kazuya Maekawa, Akio Iijima, Tetsuya Mino
  • Publication number: 20030043514
    Abstract: A read head comprises an MR element, two bias field applying layers, and two conductive layers. The two bias field applying layers are adjacent to both side portions of the MR element, and apply a bias magnetic field to the MR element along the longitudinal direction. The two conductive layers feed a sense current to the MR element, each of the conductive layers being disposed to be adjacent to one of surfaces of each of the bias field applying layers and to overlap one of surfaces of the MR element. The conductive layers are each made of a gold alloy having a resistivity of less than 22 &mgr;&OHgr;·cm and a hardness as high as or higher than the hardness of a material used for making the bias field applying layers.
    Type: Application
    Filed: July 12, 2002
    Publication date: March 6, 2003
    Applicant: TDK Corporation
    Inventors: Noriyuki Ito, Kosuke Tanaka, Koichi Terunuma
  • Publication number: 20030039080
    Abstract: A magneto-resistive device has a magneto-resistive layer laminated between electrodes. The magneto-resistive layer has a non-magnetic layer, a pinned layer and a free layer sandwiching the non-magnetic layer, and a pin layer formed on the pinned layer on the opposite side to the free layer. The pin layer is formed in a region which substantially overlaps with an effective region in a film plane direction in which a current flows in a direction substantially perpendicular to the film plane between the electrodes in a predetermined thickness, and is formed in a region which does not substantially overlap with the effective region substantially in the same thickness as the predetermined thickness or in a thickness smaller than the predetermined thickness, continuous from the region which substantially overlaps with the effective region.
    Type: Application
    Filed: August 5, 2002
    Publication date: February 27, 2003
    Applicant: TDK Corporation
    Inventors: Takeo Kagami, Norio Takahashi, Takumi Uesugi
  • Patent number: 6525912
    Abstract: A thin-film magnetic head includes a nonmagnetic lower gap layer, a nonmagnetic upper gap layer, a magnetoresistive layer, an electrode layer, and an intermediate gap layer. The magnetoresistive layer and the electrode layer are formed between the lower gap layer and the upper gap layer. The intermediate gap layer is disposed between the lower gap layer and the upper gap layer, and is formed in the region at both sides of the magnetoresistive layer in the track width direction and/or in the region behind the magnetoresistive layer in the depth direction. The length of the magnetoresistive layer in the depth direction is first determined, the width of the magnetoresistive layer in the track width direction is determined, and then the hard magnetic bias layers and the electrode layers are formed.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: February 25, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventor: Kiyoshi Sato
  • Publication number: 20030035251
    Abstract: A magnetoresistive head including a first magnetic shield, a first electrode terminal provided on the first magnetic shield and having a first width, and a magnetoresistive film provided on the first electrode terminal and having a second width less than or equal to the first width. The magnetoresistive head further includes a second electrode terminal provided on the magnetoresistive film and having a third width less than or equal to the second width, and a second magnetic shield provided on the second electrode terminal. Preferably, the magnetoresistive head further includes a plug electrode for connecting the second electrode terminal to the second magnetic shield, and a plug side wall protective insulating film for covering a side wall of the plug electrode.
    Type: Application
    Filed: March 27, 2002
    Publication date: February 20, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Hiroshi Asida, Shin Eguchi, Atsushi Tanaka, Reiko Kondo, Yutaka Shimizu
  • Publication number: 20030035250
    Abstract: Spin valve heads with overlaid leads have several advantages over butted contiguous junction designs, including larger signal output and better head stability. However, in any overlaid design there is always present at least one high resistance layer between the GMR layer and the conductive leads. This leads to an effective read width that is greater than the actual physical width. This problem has been overcome by inserting a highly conductive channeling layer between the GMR stack and the conducting lead laminate. This arrangement ensures that, at the intersection between the leads and the GMR stack, virtually all the current moves out of the free layer into the leads thereby providing an effective read width for the device that is very close to the physical read width defined by the spacing between the two leads. A process for manufacturing the device is also described.
    Type: Application
    Filed: August 17, 2001
    Publication date: February 20, 2003
    Applicant: Headway Technologies, Inc.
    Inventors: Kochan Ju, You Feng Zheng, Rod Lee
  • Patent number: 6513228
    Abstract: A method for forming a perpendicular magnetic read/write head having an air bearing surface and comprising a substantially planar top pole and a shared pole is disclosed. The steps include forming a top pole, a shared pole, and a yoke wherein the top pole and shared pole are connected distally from the air bearing surface by a yoke. A conductive coil is formed that wraps around the top pole and is positioned adjacent to the air bearing surface, with a lower portion of the coils extending between the top pole and the shared pole.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: February 4, 2003
    Assignee: Seagate Technology LLC
    Inventors: Sakhrat Khizroev, Dmitri Litvinov, Billy Wayne Crue
  • Publication number: 20030011943
    Abstract: The first and second side surfaces of either a bottom spin valve sensor or a top spin valve sensor are notched so as to enable a reduction in the magnetoresistive coefficient of side portions of the sensor beyond the track width region thereby minimizing side reading by the sensor. The first and second notches of the spin valve sensor are then filled with layers in various embodiments of the invention to complete the spin valve sensor.
    Type: Application
    Filed: July 12, 2001
    Publication date: January 16, 2003
    Inventors: Patrick Rush Webb, Mustafa Pinarbasi, Richard Hsiao, Hardayal Singh Gill
  • Patent number: 6507465
    Abstract: A magnetic head includes a magnetoresistive effect film and a pair of electrodes contacting the magnetoresistive effect film such that the electrodes overlap the magnetoresistive effect film. The magnetoresistive effect film includes a first ferromagnetic film having a direction of magnetization which is changeable, an antiferromagnetic film, a second ferromagnetic film having a direction of magnetization which is fixed by the antiferromagnetic film, and a non-magnetic conductive film disposed between the first ferromagnetic film and the second ferromagnetic film.
    Type: Grant
    Filed: October 4, 2000
    Date of Patent: January 14, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiro Nakamoto, Yoshiaki Kawato
  • Publication number: 20030007295
    Abstract: A base protective layer, a bottom shielding layer, and a bottom insulating layer 4 are formed in turn on a base made of AlTiC. Then, a magnetoresistive effective film is formed on the bottom insulating layer, and a magnetic biasing layer is formed so as to be contacted with both side surfaces of the magnetoresistive effective film which are parallel to the ABS thereof. Then, electrode layers are formed so as to be contacted with the rear surface of the magnetoresistive effective film opposite to the ABS thereof.
    Type: Application
    Filed: June 24, 2002
    Publication date: January 9, 2003
    Applicant: TDK CORPORATION
    Inventors: Akifumi Kamijima, Yoichi Ishida
  • Publication number: 20020191353
    Abstract: The inner side end faces of electrode layers are formed in a region under which bias layers are not formed, to be located behind a magnetoresistive film in the height direction. Therefore, a sensing current flowing from the electrode layers can be appropriately inhibited from shunting to the bias layers, thereby permitting the manufacture of a magnetic sensing element capable of complying with track narrowing and suppressing variations in the track width Tw.
    Type: Application
    Filed: April 17, 2002
    Publication date: December 19, 2002
    Inventor: Kiyoshi Sato
  • Patent number: 6496336
    Abstract: A structure for preventing and controlling Arcing Across Thin Dielectric Film in sputtering and other process that generate electric fields and cause arcing across conductive structures. In an embodiment, an extraneous window or two extraneous windows are formed in a second dielectric layer under at least of a portion of a lead to that a “hot spot” area is created where arcing is more likely to occur.
    Type: Grant
    Filed: August 2, 2001
    Date of Patent: December 17, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Li-Yan Zhu, Rodney Lee
  • Publication number: 20020186516
    Abstract: A transducing head has a magnetoresistive sensor and a first and a second dual path conductor/magnet structure for providing current to the magnetoresistive sensor and for stabilizing the magnetoresistive sensor. The first and the second dual path conductor/magnet structures are arranged in an abutted-junction configuration on opposite sides of the magnetoresistive sensor. Each of the first and the second dual path conductor/magnet structures has at least one bias layer and at least one conductor layer. Each bias layer is formed upon a bias seed layer positioned over one of the conductor layers. Each bias seed layer is selected to result in the bias layer formed upon it having a coercivity between about 1 kOe and about 5 kOe and an in-plane remnant squareness greater than about 0.8. Most preferably, each of the first and the second dual path conductor/magnet structures is formed of at least two conductor layers interspersed with at least one bias layer.
    Type: Application
    Filed: May 8, 2002
    Publication date: December 12, 2002
    Applicant: Seagate Technology LLC
    Inventors: David J. Larson, Eric W. Singleton, Mai A. Ghaly
  • Patent number: 6493195
    Abstract: A magnetoresistance element includes a lower electrode layer, a magnetoresistance effect layer, an upper electrode layer and a lower electrode anti-erosion/flaking layer. The lower electrode anti-erosion/flaking layer, which is formed before a photoresist layer remaining on the patterned lower electrode layer is removed, is formed around the lower electrode layer so that its edge facing the lower electrode layer will be in contact with the edge of the lower electrode layer.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: December 10, 2002
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Eizo Fukami, Hiroaki Honjo, Hisanao Tsuge, Atsushi Kamijo
  • Patent number: 6493194
    Abstract: A thin film magnetic head which includes a magnetoresistive layer selectively formed; a magnetic bias layer sandwiching said magnetoresistive layer; a pair of leads for detecting magnetic resistance; and a cap layer formed under the lead between the magnetoresistive layer. This configuration enables to accurately specify a magnetic response region by both ends of the cap layers, concentrating the current from the lead onto the magnetic response region through a tip of the cap layer for improving a S/N ratio.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: December 10, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masaya Sakaguchi, Hiroyasu Tsuji, Satoru Mitani, Tadashi Kimura, Hiroyoshi Sekiguchi
  • Patent number: 6490139
    Abstract: A magneto-resistive element comprises a first electrode, a magneto-resistive layer formed on the first electrode in which resistance is changed in accordance with magnetic field, and a second electrode layer formed on the magneto-resistive layer. The magneto-resistive layer has a first magnetic layer formed on the first electrode, a non-magnetic layer formed on the first magnetic layer, and a second magnetic layer formed on the non-magnetic layer. The average surface roughness of the first electrode is equal to or smaller than 0.3 nm. Since the first electrode has such the small average surface roughness, the non-magnetic layer formed on the first electrode layer is flattened, thus, current leakage is prevented. The first electrode is made of at least one of Ta, Zr, Ti, Hf, W, Mo, Y, V, Nb, Au, Ag, Pd, and Pt which has strong bond strength. Since the first electrode has strong bond strength, exfoliation of the first electrode from the layers contacting the first electrode does not occur.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: December 3, 2002
    Assignee: NEC Corporation
    Inventors: Kazuhiko Hayashi, Keishi Ohashi, Nobuyuki Ishiwata, Masafumi Nakada, Hisao Matsutera, Hisanao Tsuge, Atsushi Kamijo
  • Publication number: 20020154453
    Abstract: A current-perpendicular-to-the-plane (CPP) structure electromagnetic transducer element comprises upper and lower electrically-conductive lead layers. The lead layers are employed to supply an electric current to an electromagnetic transducer film. An electrically-conductive terminal piece is allowed to stand on the surface of the lower electrically-conductive lead layer. The contact established between the electrically-conductive terminal piece and the electromagnetic transducer film is allowed to define the path for the electric current. The reduced contact area of the electrically-conductive terminal piece contributes to reduction in the size or extent of the path for the electric current through the electromagnetic transducer film. The path of the electric current can be reduced in the CPP structure electromagnetic transducer element without relying on reduction in the size of the electromagnetic transducer film.
    Type: Application
    Filed: September 12, 2001
    Publication date: October 24, 2002
    Applicant: FUJITSU LIMITED
    Inventor: Junya Ikeda
  • Patent number: 6460243
    Abstract: A method of making rhodium (Rh) lead layers for a read sensor comprises a first step of obliquely ion beam sputtering the rhodium (Rh) lead layer followed by a second step of annealing. This method results in rhodium (Rh) lead layers which have reduced stress and less resistance, making them highly desirable for lead layers of a sensor in a read head.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: October 8, 2002
    Assignee: International Business Machines Corporation
    Inventor: Mustafa Pinarbasi
  • Publication number: 20020135948
    Abstract: In a magnetoresistive effect element, at least one of electrodes for supplying a current perpendicularly to the film plane of a magnetoresistive effect film is narrower than the distance between bias-applying films. The sensitivity of the magnetoresistive effect film is lower in regions thereof near the bias-applying films due to an intensive bias magnetic field from the bias-applying films. However, the electrodes are disposed in an inner region having a high sensitivity avoiding those regions with a lower sensitivity to ensure a high sensitivity. The electrodes disposed on and under the magnetoresistive effect film are pillar-shaped to concentrate the sense current such that the sense current can be concentrically supplied exclusively to the region with the high sensitivity.
    Type: Application
    Filed: March 26, 2002
    Publication date: September 26, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomomi Funayama, Masayuki Takagishi, Kohichi Tateyama, Yuichi Ohsawa, Susumu Hashimoto, Michiko Hara, Akio Hori
  • Publication number: 20020135947
    Abstract: Assuming that a distance between an upper shield layer and a lower shield layer in an area, which overlaps only a first electrode layer, but does not overlap a second electrode layer, is G1s, and a distance between the upper shield layer and the lower shield layer at a position in alignment with a center of a multilayered film is G1c, a difference in value between G1s and G1c is set to be not larger than a predetermined value, whereby an effective track (read) width can be reduced.
    Type: Application
    Filed: March 20, 2002
    Publication date: September 26, 2002
    Applicant: Alps Electric Co. Ltd.
    Inventors: Daigo Aoki, Kenji Honda, Kiyoshi Sato, Naoya Hasegawa, Yukie Nakazawa
  • Patent number: 6456465
    Abstract: A method and system for providing a magnetoresistive head that reads data from a recording media is disclosed. The method and system include providing a first shield, a second shield, a magnetoresistive sensor, and a lead. The first shield has a first end, a central portion and a second end. The first end is closer to the recording media during use than the second end. The second shield has a first end, a central portion, and a second end. The first end of the second shield is separated from the first end of the first shield by a read gap. The central portion of the second shield is separated from the central portion of the first shield by a distance that is greater than the read gap. The magnetoresistive sensor is disposed between the first shield and the second shield and has a front end and a back end. The front end of the magnetoresistive sensor is electrically coupled with the first end of the first shield or the first end of the second shield.
    Type: Grant
    Filed: November 9, 1999
    Date of Patent: September 24, 2002
    Assignee: Read-Rite Corporation
    Inventors: Ernest Anthony Louis, Ningjia Zhu, Peter Ispvan Bonyhard
  • Patent number: 6453542
    Abstract: A method for fabricating balanced shield connections for noise reduction MR/GMR read heads and an MR/MGR read head so fabricated. The present invention teaches a method for forming a balanced electrical half-bridge in parallel with the MR/GMR element of a read head so as to reduce readback noise caused by discharges between the two ends of the MR/GMR sensor element, which are at different potentials as a result of the bias current passing through the sensor, and the magnetic shields, whose potential is constant. The half-bridge is connected to each of the magnetic shields by interconnects attached to a pad at its mid-point, thus placing the shields at the same average potential as the sensor element.
    Type: Grant
    Filed: February 28, 2000
    Date of Patent: September 24, 2002
    Assignee: Headway Technologies, Inc.
    Inventor: Li-Yan Zhu
  • Publication number: 20020131216
    Abstract: In a thin film magnetic head device including a reading giant magneto-resistive thin film magnetic head element whose electric equivalent circuit is expressed by a series circuit of an equivalent voltage source and a series resistor RH and a parallel capacitor C connected in parallel with said series circuit, inductor L is connected in series with said series resistor RH and a parallel resistor R is connected in series with said parallel capacitor C. The coil L and parallel capacitor C are set such that an angular frequency &ohgr;0=1/(LC)1/2, an angular frequency &ohgr;1=1/CR and an angular frequency &ohgr;H=1/CRH satisfy conditions of &ohgr;0>&ohgr;1 and &ohgr;0>&ohgr;H, preferably &ohgr;0>>&ohgr;1 and &ohgr;0>>&ohgr;H to extend a frequency characteristic toward a high frequency range.
    Type: Application
    Filed: December 26, 2001
    Publication date: September 19, 2002
    Applicant: TDK CORPORATION
    Inventors: Isamu Sato, Koji Shimazawa, Satoru Araki
  • Patent number: 6433970
    Abstract: The present invention provides an improved current perpendicular to the plane thin film read head device and method of fabrication. With the present invention, the lower lead is formed to inhibit accumulation of redeposited lead material on CPP sensor element side walls during CPP sensor formation. In the preferred embodiment, the upper portion of the lower lead, which normally is etched during sensor element formation, is formed of a low sputter yield material to reduce redeposition flux to the sensor side walls. It is also preferred to form the upper portion of a material that also has a low value for the ratio of its sputter yield at the lead milling angle-to-its sputter yield at the side wall milling angle to inhibit redeposition accumulation on the side wall. It is preferred to clad conventional lead material with a low sputter yield ratio, low resistivity material, to inhibit side wall redeposition accumulation while also providing a low resistance lower lead.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: August 13, 2002
    Assignee: Read-Rite Corporation
    Inventors: Kenneth E. Knapp, Ronald A. Barr, Lien-Chang Wang, Benjamin P. Law, James Spallas
  • Patent number: 6433971
    Abstract: A monitor element includes electrode layers each having a front end region and a back end region extended from the front end region in the track width direction. Therefore, the width dimension of the front end region in the ABS can be set to a smaller value than conventional elements, and the height controlling process can be performed while appropriately measuring the DC resistance value of the monitor element. A magnetoresistive element also includes electrode layers having the same shape, thereby suppressing the occurrence of smearing in a thin film magnetic head, and permitting manufacture with high yield.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: August 13, 2002
    Assignee: Alps Electric Co., Ltd.
    Inventors: Kiyoshi Sato, Katsuya Sugai