Having Giant Magnetoresistive (gmr) Or Colossal Magnetoresistive (cmr) Sensor Formed Of Multiple Thin Films Patents (Class 360/324)
  • Patent number: 8411394
    Abstract: The present invention is to be capable of suppressing magnetic white noises as far as possible. A resonant magneto-resistance effect element includes a first magnetic layer whose magnetization direction is substantially parallel to a film plane, a second magnetic film whose magnetization direction is substantially perpendicular to the film plane, and a non-magnetic layer which is provided between the first and second layers.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: April 2, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Rie Sato
  • Patent number: 8393073
    Abstract: A method for constructing a magnetoresistive sensor that avoids shadowing effects of a mask structure during sensor definition. The method includes the use of an antireflective coating (ARC) and a photosensitive mask deposited there over. The photosensitive mask is formed to cover a desired sensor area, leaving non-sensor areas exposed. A reactive ion etch is performed to transfer the pattern of the photosensitive mask onto the underlying ARC layer. The reactive ion etch (RIE) is performed with a relatively high amount of platen power. The higher platen power increases ion bombardment of the wafer, thereby increasing the physical (ie mechanical) component of material removal relative to the chemical component. This increase in the physical component of material removal result in an increased rate of removal of the photosensitive mask material relative to the ion mill resistant mask.
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: March 12, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Richard Jule Contreras, Michael Feldbaum, Mustafa Michael Pinarbasi
  • Patent number: 8390963
    Abstract: A magnetoresistive read sensor is described. The sensor is a magnetically responsive stack positioned between top and bottom electrodes on an air bearing surface. Current in the sensor is confined to regions close to the air bearing surface by a first multilayer insulator structure between the stack and at least one electrode to enhance reader sensitivity.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: March 5, 2013
    Assignee: Seagate Technology LLC
    Inventors: Dimitar V. Dimitrov, Dian Song, Thu Van Nguyen, Carolyn Pitcher Van Dorn
  • Patent number: 8379350
    Abstract: An MR element includes a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer disposed between the first and second ferromagnetic layers. The spacer layer includes a nonmagnetic metal layer, a first oxide semiconductor layer, and a second oxide semiconductor layer that are stacked in this order. The nonmagnetic metal layer is made of Cu, and has a thickness in the range of 0.3 to 1.5 nm. The first oxide semiconductor layer is made of a Ga oxide semiconductor, and has a thickness in the range of 0.5 to 2.0 nm. The second oxide semiconductor layer is made of a Zn oxide semiconductor, and has a thickness in the range of 0.1 to 1.0 nm.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: February 19, 2013
    Assignee: TDK Corporation
    Inventors: Hironobu Matsuzawa, Yoshihiro Tsuchiya
  • Patent number: 8367156
    Abstract: A magnetoresistive device has an MgO (magnesium oxide) layer provided between a first ferromagnetic layer and a second ferromagnetic layer. The device is manufactured by forming a film of the MgO layer in a film forming chamber. A substance whose getter effect with respect to an oxidizing gas is large is adhered to surfaces of components provided in the chamber for forming the MgO layer. The substance having a large getter effect is a substance whose value of oxygen gas adsorption energy is 145 kcal/mol or higher. Ta (tantalum), in particular, is preferable as a substance which constitutes the magnetoresistive device.
    Type: Grant
    Filed: July 6, 2011
    Date of Patent: February 5, 2013
    Assignee: Canon Anelva Corporation
    Inventors: Yoshinori Nagamine, Koji Tsunekawa, David Djulianto Djayaprawira, Hiroki Maehara
  • Patent number: 8349195
    Abstract: A method and system provide a magnetoresistive structure from a magnetoresistive stack that includes a plurality of layers. The method and system include providing a mask that exposes a portion of the magnetoresistive stack. The mask has at least one side, a top, and a base at least as wide as the top. The method and system also include removing the portion of the magnetoresistive stack to define the magnetoresistive structure. The method and system further include providing an insulating layer. A portion of the insulating layer resides on the at least one side of the mask. The method and system further include removing the portion of the insulating layer on the at least one side of the mask and removing the mask.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: January 8, 2013
    Assignee: Western Digital (Fremont), LLC
    Inventors: Weimin Si, Liubo Hong, Honglin Zhu, Winnie Yu, Rowena Schmidt
  • Patent number: 8345390
    Abstract: An MR element according to the present invention has the superior effects that further improve an MR ratio because a structure of a spacer layer 40 is configured of a certain three-layer structure with certain materials, and at least one of a first ferromagnetic layer 30 and a second ferromagnetic layer 50 contains a certain amount of an element selected from the group of nitrogen (N), carbon (C), and oxygen (O).
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: January 1, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Shinji Hara, Tsutomu Chou, Hironobu Matsuzawa
  • Patent number: 8329320
    Abstract: A laminated high moment film with a non-AFC configuration is disclosed that can serve as a seed layer for a main pole layer or as the main pole layer itself in a PMR writer. The laminated film includes a plurality of (B/M) stacks where B is an alignment layer and M is a high moment layer. Adjacent (B/M) stacks are separated by an amorphous layer that breaks the magnetic coupling between adjacent high moment layers and reduces remanence in a hard axis direction while maintaining a high magnetic moment and achieving low values for Hch, Hce, and Hk. The amorphous material layer may be made of an oxide, nitride, or oxynitride of one or more of Hf, Zr, Ta, Al, Mg, Zn, Ti, Cr, Nb, or Si, or may be Hf, Zr, Ta, Nb, CoFeB, CoB, FeB, or CoZrNb. Alignment layers are FCC soft ferromagnetic materials or non-magnetic FCC materials.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: December 11, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Min Zheng, Fenglin Liu, Xiaomin Liu
  • Patent number: 8322022
    Abstract: A method for providing energy assisted magnetic recording (EAMR) heads is described. The method comprises bonding a plurality of lasers to a first substrate. The plurality of lasers corresponds to the plurality of EAMR heads and is for providing energy to a plurality of EAMR transducers. The method further comprises fabricating the plurality of EAMR transducers for the plurality of EAMR heads on a second substrate, bonding the first substrate to the second substrate such that the plurality of EAMR transducers and the plurality of lasers reside between the first substrate and the second substrate, removing at least one of the first substrate and the second substrate, and separating a remaining substrate into the plurality of EAMR heads.
    Type: Grant
    Filed: June 28, 2010
    Date of Patent: December 4, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Ge Yi, Hongxing Yuan, Ming Sun, Dujiang Wan
  • Patent number: 8315020
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of hydrogen molecules, hydrogen atoms, hydrogen ions, hydrogen plasma, hydrogen radicals, deuterium molecules, deuterium atoms, deuterium ions, deuterium plasma and deuterium radicals on the film submitted to the first treatment.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: November 20, 2012
    Assignees: Kabushiki Kaisha Toshiba, TDK Corporation
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Patent number: 8300356
    Abstract: A spin transfer oscillator with a seed/SIL/spacer/FGL/capping configuration is disclosed with a composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (A1/A2)X laminated spin injection layer (SIL). Field generation layer (FGL) is made of a high Bs material such FeCo. Alternatively, the STO has a seed/FGL/spacer/SIL/capping configuration. The SIL may include a FeCo layer that is exchanged coupled with the (A1/A2)X laminate (x is 5 to 50) to improve robustness. The FGL may include an (A1/A2)Y laminate (y=5 to 30) exchange coupled with the high Bs layer to enable easier oscillations. A1 may be one of Co, CoFe, or CoFeR where R is a metal, and A2 is one of Ni, NiCo, or NiFe. The STO may be formed between a main pole and trailing shield in a write head.
    Type: Grant
    Filed: May 11, 2010
    Date of Patent: October 30, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Patent number: 8283186
    Abstract: A magnetic memory device and a method for manufacturing the same are disclosed. The magnetic memory device includes a plurality of gates formed on a semiconductor substrate, a source line connected to a source/drain region shared between the gates neighboring with each other, a plurality of magnetic tunnel junctions connected to non-sharing source/drain regions of the gates on a one-to-one basis, and a bit line connected to the magnetic tunnel junctions. The magnetic memory device applies a magnetic memory cell to a memory so as to manufacture a higher-integration magnetic memory, and uses the magnetic memory cell based on a transistor of a DRAM cell, resulting in an increase in the availability of the magnetic memory.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: October 9, 2012
    Assignees: Hynix Semiconductor Inc., Grandis, Inc.
    Inventor: Hyun Jeong Kim
  • Patent number: 8277960
    Abstract: The invention relates to inorganic, intermetallic, inhomogeneous compounds having a magnetic resistance effect and an intrinsic field sensitivity of at least 7% at 1 T at room temperature. The invention further relates to a method for the production and use thereof, particularly as magnetic field sensors or in spin electronics.
    Type: Grant
    Filed: May 20, 2009
    Date of Patent: October 2, 2012
    Assignee: Johannes Gutenberg-Universität Mainz
    Inventors: Frederick Casper, Claudia Felser
  • Patent number: 8274763
    Abstract: A Lorentz Magnetoresistive sensor having an ultrathin trapping layer disposed between a quantum well structure and a surface of the sensor. The trapping layer prevents charge carriers from the surface of the sensor from affecting the quantum well structure. This allows the quantum well structure to be formed much closer to the surface of the sensor, and therefore, much closer to the magnetic field source, greatly improving sensor performance. A Lorentz Magnetoresistive sensor having a top gate electrode to hinder surface charge carriers diffusing into the quantum well, said top gate electrode being either a highly conductive ultrathin patterned metal layer or a patterned monoatomic layer of graphene.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: September 25, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Bruce Alvin Gurney, Ernesto E. Marinero
  • Patent number: 8274762
    Abstract: A system in one approach includes a sensor stack formed of a plurality of thin film layers; a shunt formed of at least some of the same layers as the sensor stack, the shunt being spaced from the sensor stack; a first lead coupled to the sensor stack and the shunt; and a second lead coupled to the sensor stack and the shunt. A method in one embodiment includes forming a plurality of thin film layers; removing a portion of the thin film layers for defining at least a portion of a sensor stack and at least a portion of a shunt spaced front the sensor stack; forming a first lead coupled to the at least a portion of the sensor stack and the at least a portion of the shunt and a second lead coupled to the at least a portion of the sensor stack and the at least a portion of the shunt. Additional systems and methods are also presented.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: September 25, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Satoru Araki, Ying Hong, Edward Hin Pong Lee, Tsann Lin, David John Seagle
  • Patent number: 8233248
    Abstract: A method and system for fabricating a magnetic transducer is described. The transducer has a device region, a field region, and a magnetoresistive stack. The method and system include providing a hard mask on the magnetoresistive stack. The hard mask is inorganic and includes a sensor portion and a line frame. The sensor portion covers a first portion of the magnetoresistive stack corresponding to a magnetoresistive structure. The line frame covers a second portion of the magnetoresistive stack in the device region. The method and system include defining the magnetoresistive structure in a track width direction using the hard mask and providing at least one hard bias material after the magnetoresistive structure is defined. A first portion of the hard bias material(s) is substantially adjacent to the magnetoresistive structure in the track width direction. The method and system also include removing a second portion of the hard bias material(s).
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: July 31, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Guanxiong Li, Wei Zhang, Ming Mao
  • Patent number: 8233247
    Abstract: A “scissoring-type” current-perpendicular-to-the-plane giant magnetoresistive (CPP-GMR) sensor has magnetically damped free layers. In one embodiment each of the two free layers is in contact with a damping layer that comprises Pt or Pd, or a lanthanoid (an element selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Th, Yb, and Lu). Each of the two free layers has one of its surfaces in contact with the sensor's electrically conducting nonmagnetic spacer layer and its other surface in contact with its associated damping layer. A nonmagnetic film may be located between each free layer and its associated damping layer. In another embodiment the damping element is present as a dopant or impurity in each of the two free layers. In another embodiment a nanolayer of the damping element is located within each of the two free layers.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: July 31, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Matthew J. Carey, Jeffrey R. Childress, Stefan Maat, Neil Smith
  • Patent number: 8228643
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of nitrogen ions, nitrogen atoms, nitrogen plasma, and nitrogen radicals on the film submitted to the first treatment.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: July 24, 2012
    Assignees: Kabushiki Kaisha Toshiba, TDK Corporation
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Patent number: 8213130
    Abstract: A magnetoresistive element includes a first electrode, a second electrode, a first magnetic layer, a second magnetic layer, a spacer layer, an oxide layer, and a metal layer. The oxide layer is provided between the first electrode and the first magnetic layer, or within the first magnetic layer, or between the first magnetic layer and the spacer layer, or within the spacer layer, or between the spacer layer and the second magnetic layer, or within the second magnetic layer, or between the second magnetic layer and the second electrode. The oxide layer includes at least one element of Zn, In, Sn, and Cd, and at least one element of Fe, Co, and Ni. The metal layer includes at least one element of Zn, In, Sn, and Cd by not less than 5 at % and not more than 80 at %, and at least one element of Fe, Co, and Ni.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: July 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Michiko Hara, Hideaki Fukuzawa, Hiromi Yuasa, Shuichi Murakami
  • Patent number: 8213129
    Abstract: A magnetoresistive element includes at least three metallic magnetic layers, at least two connection layers provided between the at least three metallic magnetic layers, each having an insulating layer and current confined paths including a metallic magnetic material penetrating the insulating layer, and electrodes which supply a current perpendicularly to a plane of a stacked film of the metallic magnetic layers and the connection layers.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: July 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 8208229
    Abstract: A magneto-resistance effect element, comprising a first magnetic layer, a first metallic layer, which is formed on said first magnetic layer, mainly containing an element selected from the group consisting of Cu, Au, Ag, a current confined layer including an insulating layer and a current path which are made by oxidizing, nitriding or oxynitriding for a second metallic layer, mainly containing Al, formed on said first metallic layer, a functional layer, which is formed on said current confined layer, mainly containing an element selected from the group consisting of Si, Hf, Ti, Mo, W, Nb, Mg, Cr and Zr, a third metallic layer, which is formed on said functional layer, mainly containing an element selected from the group consisting of Cu, Au, Ag; and a second magnetic layer which is formed on said third metallic layer.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: June 26, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8189302
    Abstract: A graphene magnetic field sensor has a ferromagnetic biasing layer located beneath and in close proximity to the graphene sense layer. The sensor includes a suitable substrate, the ferromagnetic biasing layer, the graphene sense layer, and an electrically insulating underlayer between the ferromagnetic biasing layer and the graphene sense layer. The underlayer may be a hexagonal boron-nitride (h-BN) layer, and the sensor may include a seed layer to facilitate the growth of the h-BN underlayer. The ferromagnetic biasing layer has perpendicular magnetic anisotropy with its magnetic moment oriented substantially perpendicular to the plane of the layer. The graphene magnetic field sensor based on the extraordinary magnetoresistance (EMR) effect may function as the magnetoresistive read head in a magnetic recording disk drive.
    Type: Grant
    Filed: September 11, 2010
    Date of Patent: May 29, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Bruce Alvin Gurney, Ernesto E. Marinero, Simone Pisana
  • Patent number: 8184407
    Abstract: An underlying layer (2) made of NiFeN is disposed over the principal surface of a substrate. A pinning layer (3) made of antiferromagnetic material containing Ir and Mn is disposed on the underlying layer. A reference layer (4c) made of ferromagnetic material whose magnetization direction is fixed through exchange-coupling with the pinning layer directly or via another ferromagnetic material layer, is disposed over the pinning layer. A nonmagnetic layer (7) made of nonmagnetic material is disposed over the reference layer. A free layer (8) made of ferromagnetic material whose magnetization direction changes in dependence upon an external magnetic field, is disposed over the nonmagnetic layer.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: May 22, 2012
    Assignee: Fujitsu Limited
    Inventors: Takahiro Ibusuki, Masashige Sato, Shinjiro Umehara
  • Patent number: 8184395
    Abstract: A magnetic recording and reproducing apparatus includes a metal housing, a magnetic recording medium having a magnetic recording layer, and a thin-film magnetic head having a write magnetic field production unit and a resonance magnetic field production unit. The apparatus further includes a write signal generation unit for generating the write signal, a microwave signal generation unit for generating the microwave excitation signal, a transmission unit for feeding the microwave excitation signal to the resonance magnetic field production unit and for feeding the write signal to the write magnetic field production unit, and a plurality of metal ribs, arranged in the metal housing, for forming a plurality of cavities. Each of the plurality of cavities having a rectangular horizontal section shape and having dimensions to produce no resonance at a frequency of the microwave excitation signal.
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: May 22, 2012
    Assignee: TDK Corporation
    Inventors: Hiroshi Ikeda, Saori Kajihara, Kiyoshi Noguchi, Isamu Sato
  • Patent number: 8171618
    Abstract: A method of forming a write pole for a magnetic recording device is provided. The method comprises providing a layer of magnetic material covered with a secondary hard mask layer and a patterned primary hard mask, milling at a first milling angle to transfer a pattern from the patterned primary hard mask to the secondary hard mask, and milling at a second milling angle to transfer the pattern from the secondary hard mask to the layer of magnetic material to form the write pole. The second milling angle is greater than the first milling angle. The method further comprises milling at a third milling angle to adjust a side wall angle of the write pole to about a desired side wall angle, and milling at a fourth milling angle to reduce a track width of the write pole to a desired track width.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: May 8, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Lei Wang, Ge Yi
  • Patent number: 8159791
    Abstract: A Lorentz Magnetoresistive sensor having an ultrathin trapping layer disposed between a quantum well structure and a surface of the sensor. The trapping layer prevents charge carriers from the surface of the sensor from affecting the quantum well structure. This allows the quantum well structure to be formed much closer to the surface of the sensor, and therefore, much closer to the magnetic field source, greatly improving sensor performance. A Lorentz Magnetoresistive sensor having a top gate electrode to hinder surface charge carriers diffusing into the quantum well, said top gate electrode being either a highly conductive ultrathin patterned metal layer or a patterned monoatomic layer of graphene.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: April 17, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Bruce Alvin Gurney, Ernesto E. Marinero
  • Patent number: 8149546
    Abstract: A magnetic field detecting element comprises a stack including upper and lower magnetic layers, and a non-magnetic intermediate layer sandwiched therebetween, wherein magnetization of the magnetic layers changes in accordance with an external magnetic field; upper and lower shield electrode layers sandwiching the stack in a direction of stacking, wherein the upper and lower shield electrode layers supply sense current in the direction of stacking, and magnetically shield the stack; a bias magnetic layer provided on a surface of the stack opposite to an air bearing surface, and wherein the bias magnetic layer applies a bias magnetic field to the upper and lower magnetic layers in a direction perpendicular to the air bearing surface; and insulating layers provided on both sides of the stack in a track width direction thereof, wherein the stack has a stepped portion formed at the non-magnetic intermediate layer.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: April 3, 2012
    Assignee: TDK Corporation
    Inventors: Toshiyuki Ayukawa, Daisuke Miyauchi, Koji Shimazawa, Takahiko Machita
  • Publication number: 20120075752
    Abstract: According to one embodiment, there is provided a magnetic head for a three-dimensional magnetic recording/reproducing apparatus, the head executing reading from or writing to a recording medium, utilizing a magnetic resonance, the medium including stacked layers formed of magnetic substances having different resonance frequencies, the head comprising a spin torque oscillation unit and auxiliary magnetic poles. The unit is operable to simultaneously oscillate at a plurality of frequencies to cause the magnetic resonance, when reading or writing. The magnetic poles assist the unit, when reading or writing. Further, according to another embodiment, there is provided a recording magnetic head using a high-frequency assist method and comprising a microwave magnetic field applying unit and a recording magnetic pole. The unit executes writing to a recording medium, and is formed of a plurality of spin torque oscillation elements having phases thereof synchronized. The magnetic pole assists the writing.
    Type: Application
    Filed: August 11, 2011
    Publication date: March 29, 2012
    Inventors: Rie Sato, Koichi Mizushima
  • Patent number: 8133439
    Abstract: A sensor array comprising a series connection of parallel GMR sensor stripes provides a sensitive mechanism for detecting the presence of magnetized particles bonded to biological molecules that are affixed to a substrate. The adverse effect of hysteresis on the maintenance of a stable bias point for the magnetic moment of the sensor free layer is eliminated by a combination of biasing the sensor along its longitudinal direction rather than the usual transverse direction and by using the overcoat stress and magnetostriction of magnetic layers to create a compensatory transverse magnetic anisotropy. By making the spaces between the stripes narrower than the dimension of the magnetized particle and by making the width of the stripes equal to the dimension of the particle, the sensitivity of the sensor array is enhanced.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: March 13, 2012
    Assignee: MagIC Technologies, Inc.
    Inventors: Po-Kang Wang, Xizeng Shi, Chyu-Jiuh Torng
  • Patent number: 8130476
    Abstract: A tunneling magnetic sensing element includes: a pinned magnetic layer whose direction of magnetization is pinned in one direction; an insulating barrier layer; and a free magnetic layer whose direction of magnetization changes in response to an external magnetic field. The pinned magnetic layer, the insulating barrier layer and the free magnetic layer are deposited in the named order. A first protective layer composed of a platinum-group element is disposed on the free magnetic layer, and a second protective layer composed of Ti is disposed on the first protective layer.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: March 6, 2012
    Assignee: TDK Corporation
    Inventors: Kazumasa Nishimura, Masamichi Saito, Yoshihiro Nishiyama, Hidekazu Kobayashi, Naoya Hasegawa
  • Patent number: 8111488
    Abstract: A magnetic multilayered film current element includes: at least one magnetic layer; at least one film structure containing a first insulating layer where a first opening is formed, a second insulating layer where a second opening is formed and a conductor disposed between the first insulating layer and the second insulating layer under the condition that a distance “A” between the first insulating layer and a portion of the second insulating layer at a position of the second opening is set larger than a closest distance “B” between the first insulating layer and the second insulating layer; and a pair of electrodes for flowing current to a magnetic multilayered film containing the at least one magnetic layer and the at least one film structure along a stacking direction of the magnetic multilayered film.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: February 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8111489
    Abstract: An example method for manufacturing a magneto-resistance effect element includes: forming a first magnetic layer; forming a first metallic layer, on the first magnetic layer, mainly containing an element selected from the group consisting of Cu, Au, Ag; forming a functional layer, on the first metallic layer, mainly containing an element selected from the group consisting of Si, Hf, Ti, Mo, W, Nb, Mg, Cr and Zr; forming a second metallic layer, on the functional layer, mainly containing Al; treating the second metallic layer by oxidizing, nitriding or oxynitiriding so as to form a current confined layer including an insulating layer and a current path with a conductor passing a current through the insulating layer; and forming, on the current confined layer, a second magnetic layer.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: February 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8104166
    Abstract: A method is provided for fabricating a read element with leads that overlay a top surface of a sensor of the read element. The method includes forming a mask over a sensor layer, then using the mask to define the sensor from the sensor layer. The mask is then narrowed and a lead layer is formed that overlays both ends of the top surface of the sensor without covering a center portion of the top surface.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: January 31, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Jinqiu Zhang, Ming Zhao, Mohamad T. Krounbi, Henry Yuan, Lien-Chang Wang
  • Patent number: 8105703
    Abstract: The conventional free layer in a CPP GMR or TMR read head has been replaced by a tri-layer laminate comprising Co rich CoFe, moderately Fe rich NiFe, and heavily Fe rich NiFe. The result is an improved device that has a higher MR ratio than prior art devices, while still maintaining free layer softness and acceptable magnetostriction. A process for manufacturing the device is described.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: January 31, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Hui-Chuan Wang, Min Li, Tong Zhao, Kunliang Zhang, Chyu-Jiuh Torng
  • Patent number: 8094417
    Abstract: A magnetoresistance device has a channel extending between first and second ends in a first direction comprising non-ferromagnetic semiconducting material, such as silicon, a plurality of leads connected to and spaced apart along the channel, a gate structure for applying an electric field to the channel in a second direction which is substantially perpendicular to the first direction so as to form an inversion layer in the channel and a face which lies substantially in a plane defined by the first and second directions and which is configured such that an edge of the channel runs along the face.
    Type: Grant
    Filed: February 23, 2009
    Date of Patent: January 10, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Susumu Ogawa, Andrew Troup, David Williams, Hiroshi Fukuda
  • Patent number: 8089265
    Abstract: By subdividing the free layer of a GMR/TMR device into multiple sub-elements that share common top and bottom electrodes, a magnetic detector is produced that is domain stable in the presence of large stray fields, thereby eliminating the need for longitudinal bias magnets. Said detector may be used to measure electric currents without being affected by local temperature fluctuations and/or stray fields.
    Type: Grant
    Filed: January 26, 2009
    Date of Patent: January 3, 2012
    Assignee: MagIC Technologies, Inc.
    Inventors: Yimin Guo, Po-Kang Wang
  • Patent number: 8074345
    Abstract: A method of measuring a bevel angle in a write pole comprises the step of providing a mask over a wafer containing the write pole. The mask has a first opening over the write pole and a second opening over a sacrificial region of the wafer. The sacrificial region comprises a same material as the write pole. The method further comprises the steps of performing a beveling operation on the write pole and the sacrificial region to form a first bevel in the write pole and a second bevel in the sacrificial region, and measuring an angle of the second bevel in the sacrificial region to determine the bevel angle of the write pole.
    Type: Grant
    Filed: May 18, 2009
    Date of Patent: December 13, 2011
    Assignee: Western Digital (Fremont), LLC
    Inventors: Alexandre Anguelouch, Donghong Li
  • Patent number: 8076012
    Abstract: Disclosed are a magnetic thin film capable of providing a high uniaxial magnetic anisotropy, Ku, while suppressing the saturation magnetization Ms thereof, and a method for forming the film; and also disclosed are various devices to which the magnetic thin film is applied. The magnetic thin film comprises a Co-M-Pt alloy having an L11-type ordered structure (wherein M represents one or more metal elements except Co and Pt). For example, the Co-M-Pt alloy is a Co—Ni—Pt alloy of which the composition comprises from 10 to 35 at. % of Co, from 20 to 55 at. % of Ni and a balance of Pt. The magnetic thin film is applicable to perpendicular magnetic recording media, tunnel magneto-resistance (TMR) devices, magnetoresistive random access memories (MRAM), microelectromechanical system (MEMS) devices, etc.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: December 13, 2011
    Assignees: Tohoku University, Fuji Electric Co., Ltd.
    Inventors: Takehito Shimatsu, Hideo Sato, Osamu Kitakami, Satoshi Okamoto, Hajime Aoi, Hiroyasu Kataoka
  • Publication number: 20110299198
    Abstract: The present invention relates to a magnetic recording medium comprising a magnetic layer comprising a ferromagnetic powder and a binder on a nonmagnetic support, wherein the magnetic layer has a thickness ? ranging from 10 to 80 nm, a product, Mr?, of a residual magnetization Mr of the magnetic layer and the thickness ? of the magnetic layer is equal to or greater than 1 mA but less than 5 mA, a ratio, Sdc/Sac, of an average area Sdc of magnetic clusters in a DC demagnetized state to an average area Sac of magnetic clusters in an AC demagnetized state as measured by a magnetic force microscope, MFM, ranges from 0.8 to 2.0.
    Type: Application
    Filed: May 4, 2011
    Publication date: December 8, 2011
    Applicant: FUJIFILM Corporation
    Inventors: Toshio TADA, Takeshi Harasawa
  • Patent number: 8072711
    Abstract: A chemical or corrosive environment sensing system, comprising a giant magnetoresistive effect device having at least one environmentally exposed film, and a device, for sensing changes in the GMR effect device resulting from environmental exposure of the at least one environmentally exposed film. The film may be reversibly or irreversibly altered by the exposure, and is preferably nano-textured to alter a reaction rate and surface area. The sensor may be enzyme linked, that is, respond to an enzyme reaction product rather than the substrate directly. The GMR property altered and/or sensed may be, for example, a lower or upper switching field, an electrical resistance, and the GMR value. The device may be used as a sensor or as part of a control system.
    Type: Grant
    Filed: August 2, 2006
    Date of Patent: December 6, 2011
    Inventor: Jian-Qing Wang
  • Patent number: 8066897
    Abstract: A method for manufacturing a current perpendicular to plane magnetoresistive sensor that allows for dynamic adjustment of free layer biasing to compensate for variations in thickness of an electrically insulating layer that separates the hard bias layers from the free layer. During fabrication of the sensor, the actual thickness of the insulation layers is measured. Then, to maintain a desired magnetic stabilization of the free layer one of three options can be utilized. Option one; adjust the stripe height target to maintain the desired magnetic stabilization. Option two; adjust the hard magnet thickness to maintain the desired magnetic stabilization. Option three; use a combination of option one and option two, adjusting both the stripe height target and the hard magnet thickness to maintain the desired magnetic stabilization.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: November 29, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Arley Cleveland Marley
  • Patent number: 8065786
    Abstract: Provided is a manufacturing method of heat-assisted magnetic recording head, in which a light source unit can be easily joined to a slider with sufficiently high accuracy, under avoiding the excessive mechanical stress. The manufacturing method comprises the steps of: moving relatively the light source unit and the slider, while applying a sufficient voltage between an upper electrode of the light source and an electrode layer provided in the slider; and setting the light source unit and the slider in desired positions in a direction perpendicular to the element-integration surface of the slider substrate. The desired positions are positions where the light source just emits due to a surface contact between: the protruded portion of the lower surface of the light source; and the upper surface of the electrode layer, which is a portion of the wall surface of a step formed on the head part.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: November 29, 2011
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yasuhiro Ito, Eiji Komura, Seiichi Takayama, Kosuke Tanaka
  • Patent number: 8059373
    Abstract: Magnetic sensing chips and methods of fabricating the magnetic sensing chips are disclosed. A magnetic sensing chip as described herein includes an EMR sensor formed on a substrate from multiple semiconductor layers. One or more of the semiconductor layers form a quantum well comprising a two-dimensional electron gas (2DEG) or hole gas (2DHG). The magnetic sensing chip also includes one or more transistors formed on the substrate from the multiple semiconductor layers. The transistor(s) likewise include a quantum well comprising a 2DEG or 2DHG. The EMR sensor and the transistor(s) are connected by one or more connections so that the transistor(s) amplifies data signals from the EMR sensor.
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: November 15, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Liesl Folks, Robert E. Fontana, Jr., Bruce A. Gurney, Klaas B. Klaassen, Stefan Maat
  • Patent number: 8054588
    Abstract: A tunnel magnetoresistive element includes a laminate including a pinned magnetic layer, an insulating barrier layer, and a free magnetic layer. The insulating barrier layer is composed of Ti—Mg—O or Ti—O. The free magnetic layer includes an enhancement sublayer, a first soft magnetic sublayer, a nonmagnetic metal sublayer, and a second soft magnetic sublayer. For example, the enhancement sublayer is composed of Co—Fe, the first soft magnetic sublayer and the second soft magnetic sublayer are composed of Ni—Fe, and the nonmagnetic metal sublayer is composed of Ta. The total thickness of the average thickness of the enhancement sublayer and the average thickness of the first soft magnetic sublayer is in the range of 25 to 80 angstroms. Accordingly, the tunneling magnetoresistive element can consistently have a higher rate of resistance change than before.
    Type: Grant
    Filed: February 11, 2011
    Date of Patent: November 8, 2011
    Assignee: Alps Electric Co., Ltd.
    Inventors: Kazumasa Nishimura, Ryo Nakabayashi, Yosuke Ide, Hasahiko Ishizone, Masamichi Saito, Naoya Hasegawa, Yoshihiro Nishiyana, Akio Hanada, Hidekezu Kobayashi
  • Patent number: 8054587
    Abstract: An MR element includes a lower shield layer, a magnetization free function part stacked on the lower shield layer, an upper shield layer stacked on the magnetization free function part, a nonmagnetic intermediate layer stacked on a surface, that is opposite to a magnetically sensitive surface, of the magnetization free function part, and a magnetization fixed function part stacked on the nonmagnetic intermediate layer. The nonmagnetic intermediate layer and the magnetization fixed function part are formed only within an outer region of the magnetization free function part, located opposite side to the magnetically sensitive surface.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: November 8, 2011
    Assignee: TDK Corporation
    Inventor: Takumi Yanagisawa
  • Patent number: 8049998
    Abstract: A magnetoresistance effect device includes: an insulator layer; a first and second ferromagnetic layer laminated to sandwich the insulator layer; a magnetic bias layer laminated with the second ferromagnetic layer; and a connecting section formed discontinuously on a side face of the insulator layer. The connecting section is not interposed between the second ferromagnetic layer and the magnetic bias layer. The connecting section is made of a ferromagnetic material, and electrically connecting between the first ferromagnetic layer and the second ferromagnetic layer. A method for manufacturing a magnetoresistance effect device includes: laminating a first and second ferromagnetic layer to sandwich an insulator layer, and laminating a magnetic bias layer with the second ferromagnetic layer; and forming a connecting section for electrically connecting between the first ferromagnetic layer and the second ferromagnetic layer by discontinuously forming a ferromagnetic material on a side face of the insulator layer.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: November 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuichi Ohsawa, Shiho Nakamura
  • Patent number: 8045294
    Abstract: An opening (3) is formed on a surface of a metal film (2), a plurality of axes (4, 5, 6, 7) cross each other substantially perpendicularly at the opening (3), a plurality of periodic grooves (8, 9, 10, 11) are provided for respective axes (4, 5, 6, 7), and each of the periodic grooves (8, 9, 10, 11) includes a plurality of grooves (8-n, 9-n, 10-n, and 11-n) substantially perpendicular to the axis for which each periodic groove is provided, and the periodic grooves (8, 9, 10, 11) is positioned point-symmetrically with respect to the opening (3).
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: October 25, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tomoki Ono, Shintaro Miyanishi, Kousuke Innami, Yoshiteru Murakami
  • Patent number: 8035927
    Abstract: An extraordinary magnetoresistive sensor (EMR sensor) having a lead structure that is self aligned with a magnetic shunt structure. To form an EMR sensor according to an embodiment of the invention, a plurality of layers are deposited to form quantum well structure such as a two dimensional electron gas structure (2DEG). A first mask structure is deposited having two openings, and a material removal process is performed to remove portions of the sensor material from areas exposed by the openings. The distance between the two openings in the first mask defines a distance between a set of leads and the shunt structure. A non-magnetic metal is then deposited. A second mask structure is then formed to define shape of the leads.
    Type: Grant
    Filed: January 28, 2008
    Date of Patent: October 11, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Thomas Dudley Boone, Jr., Liesl Folks, Robert E. Fontana, Jr., Bruce Alvin Gurney, Jordan Asher Katine, Sergio Nicoletti
  • Patent number: 8031444
    Abstract: The semiconductor oxide layer that forms a part of the spacer layer in the inventive giant magnetoresistive device (CPP-GMR device) is composed of zinc oxide of wurtzite structure that is doped with a dopant given by at least one metal element selected from the group consisting of Zn, Ge, V, and Cr in a content of 0.05 to 0.90 at %: there is the advantage obtained that ever higher MR ratios are achievable while holding back an increase in the area resistivity AR.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: October 4, 2011
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Tomohito Mizuno, Koji Shimazawa, Yoshihiro Tsuchiya, Shinji Hara, Hironobu Matsuzawa
  • Publication number: 20110235216
    Abstract: A read head having an improved longitudinal bias stack for stabilizing the sense layer structure of a CPP read sensor is proposed. The longitudinal bias stack is separated by an insulation layer from the CPP read sensor in each of two side regions, and is sandwiched together with the insulation layer and the CPP read sensor between lower and upper ferromagnetic shields in the read head. In a preferred embodiment of the invention, the longitudinal bias stack mainly comprises an Fe—Pt longitudinal bias layer without any seed layers, and thus the thickness of the insulation layer alone defines a spacing between the Fe—Pt longitudinal bias layer and the CPP read sensor. Since the Fe—Pt longitudinal bias layer without any seed layers exhibits good in-plane hard-magnetic properties after annealing and the spacing is narrow, the stabilization scheme is effective.
    Type: Application
    Filed: March 26, 2010
    Publication date: September 29, 2011
    Inventor: Tsann Lin