Having Giant Magnetoresistive (gmr) Or Colossal Magnetoresistive (cmr) Sensor Formed Of Multiple Thin Films Patents (Class 360/324)
  • Patent number: 8922954
    Abstract: A data reader can be configured with at least a magnetically responsive lamination that has a first portion with a first stripe height from an air bearing surface (ABS) and a second portion with a different second stripe height from the ABS. The first portion can be constructed to have a back edge surface shaped at a predetermined angle relative to the ABS by a back edge feature.
    Type: Grant
    Filed: May 6, 2013
    Date of Patent: December 30, 2014
    Assignee: Seagate Technology LLC
    Inventors: Xin Cao, Frances Paula McElhinney, Jiansheng Xu, Marcus Winston Ormston
  • Patent number: 8922951
    Abstract: Various embodiments may be generally directed to a data storage device with at least a magnetic element having a magnetic stack positioned adjacent to and separated from at least one side shield on an air bearing surface (ABS). The side shield can be configured with a predetermined anisotropy variation along a down-track direction.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: December 30, 2014
    Assignee: Seagate Technology LLC
    Inventors: Victor Boris Sapozhnikov, Mohammed Shariat Ullah Patwari, Shaun Eric McKinlay, Konstantin Rudolfovich Nikolaev, Eric Walter Singleton, Jae-Young Yi
  • Publication number: 20140362477
    Abstract: According to one embodiment, a magneto-resistance effect device includes: a multilayer structure having a cap layer; a magnetization pinned layer; a magnetization free layer provided between the cap layer and the magnetization pinned layer; a spacer layer provided between the magnetization pinned layer and the magnetization free layer; a function layer which is provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer, the function layer having oxide containing at least one element selected from Zn, In, Sn and Cd, and at least one element selected from Fe, Co and Ni; and a pair of electrodes for applying a current perpendicularly to a film plane of the multilayer structure.
    Type: Application
    Filed: August 26, 2014
    Publication date: December 11, 2014
    Inventors: Yoshihiko FUJI, Hideaki FUKUZAWA, Hiromi YUASA, Michiko HARA, Shuichi MURAKAMI
  • Patent number: 8884616
    Abstract: Embodiments relate to xMR sensors, in particular AMR and/or TMR angle sensors with an angle range of 360 degrees. In embodiments, AMR angle sensors with a range of 360 degrees combine conventional, highly accurate AMR angle structures with structures in which an AMR layer is continuously magnetically biased by an exchange bias coupling effect. The equivalent bias field is lower than the external rotating magnetic field and is applied continuously to separate sensor structures. Thus, in contrast with conventional solutions, no temporary, auxiliary magnetic field need be generated, and embodiments are suitable for magnetic fields up to about 100 mT or more. Additional embodiments relate to combined TMR and AMR structures. In such embodiments, a TMR stack with a free layer functioning as an AMR structure is used. With a single such stack, contacted in different modes, a high-precision angle sensor with 360 degrees of uniqueness can be realized.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: November 11, 2014
    Assignee: Infineon Technologies AG
    Inventors: Juergen Zimmer, Klemens Pruegl
  • Patent number: 8860159
    Abstract: A spintronic electronic apparatus having a multilayer structure. The apparatus includes a substrate, having disposed in succession upon the substrate; a bottom interface layer; a pinned layer; a tunneling barrier; a free layer; and a top interface layer, wherein the apparatus operates as a non-resonant magnetic tunnel junction in a large amplitude, out-of-plane magnetization precession regime having weakly current dependent, large diode volt-watt sensitivity when external microwave signals that exceed a predetermined threshold current and have a frequency that is lower than a predetermined level excite the magnetization precession.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: October 14, 2014
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Thomas J. Meitzler, Elena N. Bankowski, Michael Nranian, Ilya N. Krivorotov, Andrei N. Slavin, Vasyl S. Tyberkevych
  • Patent number: 8837092
    Abstract: An apparatus can be generally directed to a magnetic stack having a magnetically free layer positioned on an air bearing surface (ABS). The magnetically free layer can be biased to a predetermined magnetization in various embodiments by a biasing structure that is coupled with the magnetically free layer and positioned distal the ABS.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: September 16, 2014
    Assignee: Seagate Technology LLC
    Inventors: Mark William Covington, Dimitar Velikov Dimitrov, Dian Song
  • Patent number: 8829901
    Abstract: A method to measure a magnetic field is provided. The method includes applying an alternating drive current to a drive strap overlaying a magnetoresistive sensor to shift an operating point of the magnetoresistive sensor to a low noise region. An alternating magnetic drive field is generated in the magnetoresistive sensor by the alternating drive current. When the magnetic field to be measured is superimposed on the alternating magnetic drive field in the magnetoresistive sensor, the method further comprises extracting a second harmonic component of an output of the magnetoresistive sensor. The magnetic field to be measured is proportional to a signed amplitude of the extracted second harmonic component.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: September 9, 2014
    Assignee: Honeywell International Inc.
    Inventor: Bharat B. Pant
  • Patent number: 8830616
    Abstract: A write head for a magnetic storage device includes a writing tip comprising a magnetic material, a write pulse generator configured to generate a write pulse signal comprising a varying voltage bias between the magnetic storage device and the writing tip. The write pulse signal comprising one or more write pulses effective to tunnel electrons from the writing tip to the magnetic storage device. The data stream generator configured to provide a data stream signal to the writing tip where the data stream signal is operative to vary spin polarity in the electrons from a first polarity to a second polarity.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: September 9, 2014
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Frank Sinclair, Alexander C. Kontos, Rajesh Dorai
  • Patent number: 8824108
    Abstract: According to one embodiment, a magneto-resistance effect element includes: a first electrode; a second electrode; a first magnetic layer provided between the first and the second electrodes; a second magnetic layer provided between the first magnetic layer and the second electrode; and an oxide layer of a metal oxide provided between the first magnetic layer and the second magnetic layer. The oxide layer includes wustite crystal grains of a wustite structure with a (1 1 1) plane orientation containing iron. A lattice spacing of a (1 1 1) plane of the wustite crystal grains is not less than 0.253 nanometers and not more than 0.275 nanometers.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: September 2, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Michiko Hara, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8810974
    Abstract: The present invention is directed to align crystal c-axes in magnetic layers near two opposed junction wall faces of a magnetoresistive element so as to be almost perpendicular to the junction wall faces. A magnetic sensor stack body has, on a substrate, a magnetoresistive element whose electric resistance fluctuates when a bias magnetic field is applied and, on sides of opposed junction wall faces of the magnetoresistive element, field regions including magnetic layers for applying the bias magnetic field to the element. The magnetoresistive element has at least a ferromagnetic stack on a part of an antiferromagnetic layer, and width of an uppermost face of the ferromagnetic stack along a direction in which the junction wall faces are opposed to each other is smaller than width of an uppermost face of the antiferromagnetic layer in the same direction.
    Type: Grant
    Filed: August 4, 2010
    Date of Patent: August 19, 2014
    Assignee: Canon Anelva Corporation
    Inventors: Abarra Einstein Noel, Masahiro Suenaga, Yoshinori Ota, Tetsuya Endo
  • Patent number: 8779538
    Abstract: In one embodiment, a magnetic element for a semiconductor device includes a reference layer, a free layer, and a nonmagnetic spacer layer disposed between the reference layer and the free layer. The nonmagnetic spacer layer includes a binary, ternary, or multi-nary alloy oxide material. The binary, ternary, or multi-nary alloy oxide material includes MgO having one or more additional elements selected from the group consisting of: Ru, Al, Ta, Tb, Cu, V, Hf, Zr, W, Ag, Au, Fe, Co, Ni, Nb, Cr, Mo, and Rh.
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: July 15, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Eugene Youjun Chen, Xueti Tang
  • Patent number: 8780507
    Abstract: A transducer according to one embodiment comprises a first ferromagnetic layer; a second ferromagnetic layer; and an electrically conductive layer positioned between the ferromagnetic layers; wherein a length of the first ferromagnetic layer in a first direction parallel to a plane of deposition thereof is greater than a length of the electrically conductive layer in the first direction such that a first end of the first ferromagnetic layer extends beyond an end of the electrically conductive layer in the first direction, wherein an electrical current enters or exits the end of the first ferromagnetic layer that extends beyond the end of the electrically conductive layer in the first direction. Additional transducer structures, and systems implementing such transducers, are also disclosed.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: July 15, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Ying Hong, Kochan Ju, Ching Hwa Tsang
  • Patent number: 8780508
    Abstract: A magnetic element is generally provided that can be implemented as a transducing head. Various embodiments may configure a magnetic stack having a magnetically free layer with a predetermined magnetization. A side shield lamination can be separated from the magnetic stack on an air hearing surface (ABS) and biased to a bias magnetization that opposes the predetermined magnetization.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: July 15, 2014
    Assignee: Seagate Technology LLC
    Inventors: Dimitar Velikov Dimitrov, Dian Song, Mark William Covington
  • Patent number: 8773821
    Abstract: A mixed anisotropy magnetic field sensor includes a first magnetic material film having in-plane anisotropy with a first magnetic easy axis that is in-plane, a second magnetic material film having out-of-plane anisotropy with a second magnetic easy axis that is perpendicular to the first magnetic easy axis of the first magnetic material film, and a non-magnetic spacer between the first magnetic material film and the second magnetic material film. The first magnetic material film has a magnetization oriented in a first magnetization orientation parallel to the first magnetic easy axis in the presence of no applied magnetic field, and the second magnetic material film has a magnetization oriented in a second magnetization orientation parallel to the second magnetic easy axis in the presence of no applied magnetic field.
    Type: Grant
    Filed: October 5, 2012
    Date of Patent: July 8, 2014
    Assignee: NVE Corporation
    Inventor: Joseph E. Davies
  • Patent number: 8749925
    Abstract: Read elements and associated methods of fabrication are disclosed. During fabrication of the read element, and more particularly, the fabrication of the hard bias magnets, a non-magnetic sacrificial layer is deposited on top of the hard bias material. When a CMP process is subsequently performed, the sacrificial layer is polished instead of the hard bias material. The thicknesses of the hard bias magnets are not affected by the CMP process, but are rather defined by the deposition process of the hard bias material. As a result, the variations in the CMP process will not negatively affect the magnetic properties of the hard bias magnets so that they are able to provide substantially uniform effective magnetic fields to bias the free layer of the magnetoresistance (MR) sensor of the read element.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: June 10, 2014
    Assignee: HGST Netherlands, B.V.
    Inventors: Ying Hong, Ming Jiang, John Westwood
  • Patent number: 8743511
    Abstract: A method and apparatus for increasing the electrical resistivity and corrosion resistance of the material forming a spacer layer in current-perpendicular-to-the-plane (CPP) giant magnetoresistive (GMR) sensors. The increased resistivity of the spacer layer, and thus, the CPP-GMR sensor permits a larger voltage across the sensor and a higher signal-to-noise ratio. The increased corrosion resistance of the spacer layer minimizes the effects of exposing the spacer layer to corrosive materials during fabrication. For example, adding tin to silver to form a metallic alloy spacer layer increases the corrosion resistance of the spacer layer and the electrical resisitivity of the CPP-GMR sensor relative to a spacer layer consisting solely of silver. The Ag—Sn alloy permits a larger current to flow through the sensor, which increases the signal-to-noise ratio.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: June 3, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Jeffrey R. Childress, John C. Read, Neil Smith
  • Patent number: 8728825
    Abstract: A GMR sensor stripe 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 stripe free layer is eliminated by a combination of biasing the sensor stripe 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 connecting the stripes in an array and 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: March 12, 2012
    Date of Patent: May 20, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Po-Kang Wang, Xizeng Shi, Chyu-Jiuh Torng
  • Patent number: 8717715
    Abstract: A spin accumulation magnetic sensor having improved signal strength and efficiency. The spin accumulation magnetic sensor has a detector structure and a spin injection structure and has a non-magnetic, electrically conductive layer extending between the spin injection structure and the detector structure. The detector structure has first and second free layers arranged such that the non-magnetic, electrically conductive layer extends between them and so that they are magnetically anti-parallel coupled with one another. The spin injection structure can also include first and second magnetic layers with the electrically conductive layer extending between them and with the first magnetic layer being pinned and the second magnetic layer being anti-parallel coupled with the first magnetic layer.
    Type: Grant
    Filed: December 13, 2012
    Date of Patent: May 6, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Daisuke Sato, Masaki Yamada
  • Patent number: 8710604
    Abstract: In accordance with an embodiment, a magnetoresistive element includes a lower electrode, a first magnetic layer on the lower electrode, a first diffusion prevention layer on the first magnetic layer, a first interfacial magnetic layer on the first metal layer, a nonmagnetic layer on the first interfacial magnetic layer, a second interfacial magnetic layer on the nonmagnetic layer, a second diffusion prevention layer on the second interfacial magnetic layer, a second magnetic layer on the second diffusion prevention layer, and an upper electrode layer on the second magnetic layer. The ratio of a crystal-oriented part to the other part in the second interfacial magnetic layer is higher than the ratio of a crystal-oriented part to the other part in the first interfacial magnetic layer.
    Type: Grant
    Filed: March 20, 2012
    Date of Patent: April 29, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Yamakawa, Katsuaki Natori, Daisuke Ikeno, Tadashi Kai
  • Patent number: 8711526
    Abstract: A magnetic element is generally provided that can be implemented as a transducing head. Various embodiments may configure a magnetic stack to be separated from a side shield lamination on an air bearing surface (ABS). The side shield lamination can be constructed to have a plurality of magnetic and non-magnetic layers each coupled to a top shield.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: April 29, 2014
    Assignee: Seagate Technology LLC
    Inventors: Levent Colak, Mark William Covington, Dimitar Velikov Dimitrov, Mark Thomas Kief, Anthony Mack, Dian Song
  • Publication number: 20140098443
    Abstract: A mixed anisotropy magnetic field sensor includes a first magnetic material film having in-plane anisotropy with a first magnetic easy axis that is in-plane, a second magnetic material film having out-of-plane anisotropy with a second magnetic easy axis that is perpendicular to the first magnetic easy axis of the first magnetic material film, and a non-magnetic spacer between the first magnetic material film and the second magnetic material film. The first magnetic material film has a magnetization oriented in a first magnetization orientation parallel to the first magnetic easy axis in the presence of no applied magnetic field, and the second magnetic material film has a magnetization oriented in a second magnetization orientation parallel to the second magnetic easy axis in the presence of no applied magnetic field.
    Type: Application
    Filed: October 5, 2012
    Publication date: April 10, 2014
    Applicant: NVE CORPORATION
    Inventor: Joseph E. Davies
  • Patent number: 8685491
    Abstract: According to one embodiment, a method of manufacturing a magnetoresistive element includes a layered structure and a pair of electrodes, the layered structure including a cap layer, a magnetization pinned layer, a magnetization free layer, a spacer layer and a functional layer provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer and including an oxide, the method including forming a film including a base material of the functional layer, performing an oxidation treatment on the film using a gas containing oxygen in a form of at least one selected from the group consisting of molecule, ion, plasma and radical, and performing a reduction treatment using a reducing gas on the film after the oxidation treatment.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: April 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiko Takeo, Yoshihiko Fuji, Hiromi Yuasa, Michiko Hara, Shuichi Murakami, Hideaki Fukuzawa
  • Patent number: 8675309
    Abstract: A spin-torque oscillator with antiferromagnetically-coupled free layers has at least one of the free layers with increased magnetic damping. The Gilbert magnetic damping parameter (?) is at least 0.05. The damped free layer may contain as a dopant one or more damping elements selected from the group consisting of Pt, Pd and the 15 lanthanide elements. The free layer damping may also be increased by a damping layer adjacent the free layer. One type of damping layer may be an antiferromagnetic material, like a Mn alloy. As a modification to the antiferromagnetic damping layer, a bilayer damping layer may be formed of the antiferromagnetic layer and a nonmagnetic metal electrically conductive separation layer between the free layer and the antiferromagnetic layer. Another type of damping layer may be one formed of one or more of the elements selected from Pt, Pd and the lanthanides.
    Type: Grant
    Filed: April 6, 2013
    Date of Patent: March 18, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Patrick Mesquita Braganca, Bruce Alvin Gurney
  • Patent number: 8659855
    Abstract: A magnetoresistive read sensor with improved sensitivity and stability is described. The sensor is a trilayer stack positioned between two electrodes. The trilayer stack has two free layers separated by a nonmagnetic layer and a biasing magnet positioned at the rear of the stack and separated from the air bearing surface. Current in the sensor is confined to regions close to the air bearing surface by an insulator layer to enhance reader sensitivity.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: February 25, 2014
    Assignee: Seagate Technology LLC
    Inventors: Dimitar Velikov Dimitrov, Dion Song, Mark William Covington, James Wessel
  • Patent number: 8655302
    Abstract: A demodulator of an FM signal modulated about a carrier frequency with a modulation frequency has an RF oscillator configured to be synchronized, under identical conditions of operation, with oscillations at first and second frequencies used in the FM signal to encode respective pieces of information. The oscillator has a magnetoresistive device; and a low-pass filter connected to an output electrode of the magnetoresistive device to filter an oscillating signal, generated by the oscillator and to a rendering terminal to provide, as a demodulated electrical signal, the filtered signal, the cut-off frequency fc at ?3 dB of this filter being strictly lower than the frequency and higher than the modulation frequency.
    Type: Grant
    Filed: April 18, 2012
    Date of Patent: February 18, 2014
    Assignee: Commissariat a l'Energie Atomique et aux Energies Alternatives
    Inventors: Michaël Quinsat, Marie-Claire Cyrille, Ursula Ebels, Jean-Philippe Michel
  • Patent number: 8637947
    Abstract: A memory element includes a layered structure and a negative thermal expansion material layer. The layered structure includes a memory layer, a magnetization-fixed layer, and an intermediate layer. The memory layer has magnetization perpendicular to a film face in which a magnetization direction is changed depending on information, and includes a magnetic layer having a positive magnetostriction constant. The magnetization direction is changed by applying a current in a lamination direction of the layered structure to record the information in the memory layer. The magnetization-fixed layer has magnetization perpendicular to a film face that becomes a base of the information stored in the memory layer. The intermediate layer is formed of a non-magnetic material and is provided between the memory layer and the magnetization-fixed layer.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: January 28, 2014
    Assignee: Sony Corporation
    Inventors: Kazutaka Yamane, Masanori Hosomi, Hiroyuki Ohmori, Kazuhiro Bessho, Yutaka Higo, Tetsuya Asayama, Hiroyuki Uchida
  • Patent number: 8631561
    Abstract: The present invention generally relates to fabricating a bond pad for electrically connecting a laser diode to a slider and a TAR head in a HDD. The bond pad is deposited on a surface of the head that is perpendicular to the air bearing surface (ABS). The head is diced and lapped to expose the bond pad on a top surface of the head and mounted on a slider. The laser diode and a sub-mount may be coupled to the top surface of the slider—i.e., the surface opposite the ABS—by connecting to the bond pads. Specifically, both the laser diode and the sub-mount have electrodes thereon that are perpendicular to the bond pads. Conductive bonding material is used to bond the laser diode and the sub-mount to the bond pads.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: January 21, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Christian René Bonhôte, Linden James Crawforth, Toshiki Hirano, Fu-Ying Huang, Neil Leslie Robertson, Barry Cushing Stipe
  • Patent number: 8630070
    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: Grant
    Filed: August 11, 2011
    Date of Patent: January 14, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Rie Sato, Koichi Mizushima
  • Publication number: 20140009854
    Abstract: According to one embodiment, a magneto-resistance effect device includes: a multilayer structure having a cap layer; a magnetization pinned layer; a magnetization free layer provided between the cap layer and the magnetization pinned layer; a spacer layer provided between the magnetization pinned layer and the magnetization free layer; a function layer which is provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer, the function layer having oxide containing at least one element selected from Zn, In, Sn and Cd, and at least one element selected from Fe, Co and Ni; and a pair of electrodes for applying a current perpendicularly to a film plane of the multilayer structure.
    Type: Application
    Filed: September 12, 2013
    Publication date: January 9, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko FUJI, Hideaki FUKUZAWA, Hiromi YUASA, Michiko HARA, Shuichi MURAKAMI
  • Patent number: 8618793
    Abstract: A tool for testing a magnetic disk for use in a magnetic disk drive. The tool detects surface defects or asperities by detecting a change in electrical resistance corresponding to a temperature change in a thermally sensitive layer. The apparatus includes a slider body having a thermally insulating layer formed on an air bearing surface of the slider body and a thermal sensor layer formed on the thermally insulating layer. The thermally insulating layer prevents thermal heat spikes in the thermal sensor layer (such as resulting from contact with an asperity) from dissipating quickly into the slider body itself. The thermal sensor layer is a material that exhibits a change in electrical resistance in response to a change in temperature and is preferably a PTC thermistor material which exhibits a large change in electrical resistance when a transition temperature has been reached.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: December 31, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, John S. Hopkins, Kenneth E. Johnson
  • Patent number: 8619393
    Abstract: In certain embodiments, a magnetic had includes a top shield and a bottom shield positioned at an air bearing surface. A polarizer and a nonmagnetic layer are positioned between the top and bottom shields. An analyzer is positioned adjacent the nonmagnetic layer at a distance recessed from the air bearing surface. Current travels through the top shield, polarizer, nonmagnetic layer, and first analyzer.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: December 31, 2013
    Assignee: Seagate Technology LLC
    Inventor: Scott Stokes
  • Patent number: 8617644
    Abstract: A method for making a current-perpendicular-to the-plane giant magnetoresistance (CPP-GMR) sensor with a Heusler alloy pinned layer on the sensor's Mn-containing antiferromagnetic pinning layer uses two annealing steps. A layer of a crystalline non-Heusler alloy ferromagnetic material, like Co or CoFe, is deposited on the antiferromagnetic pinning layer and a layer of an amorphous X-containing ferromagnetic alloy, like a CoFeBTa layer, is deposited on the Co or CoFe crystalline layer. After a first in-situ annealing of the amorphous X-containing ferromagnetic alloy, the Heusler alloy pinned layer is deposited on the amorphous X-containing ferromagnetic layer and a second high-temperature annealing step is performed to improve the microstructure of the Heusler alloy pinned layer.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: December 31, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Matthew J. Carey, Shekar B Chandrashekariaih, Jeffrey R. Childress, Young-suk Choi, John Creighton Read
  • Patent number: 8619467
    Abstract: Multi-period structures exhibiting giant magnetoresistance (GMR) are described in which the exchange coupling across the active interfaces of the structure is ferromagnetic.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: December 31, 2013
    Assignee: Integrated Magnetoelectronics
    Inventors: E. James Torok, Richard Spitzer, David L. Fleming, Edward Wuori
  • Patent number: 8610512
    Abstract: A synthesizer includes a second frequency-synthesizing stage comprising a radiofrequency oscillator configured to oscillate at a frequency ?fo when it is synchronized with a signal s0(t), where ? is a rational number different from one such that ?f0=ft. The radiofrequency oscillator has a magnetoresistive device within which there flows a spin-polarized electrical current to generate a signal st(t) oscillating at the frequency ft on an output electrode connected to the rendering terminal. This device is formed by a stack of magnetic and non-magnetic layers, a synchronization terminal for synchronizing the frequency of the oscillating signal st(t) with the frequency of the signal received at the synchronization terminal. The synchronization terminal being connected to the output terminal of the first stage to receive the signal s0(t).
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: December 17, 2013
    Assignee: Commissariat a l'Energie Atomique et aux Energies Alternatives
    Inventors: Jean-Philippe Michel, Michaël Quinsat
  • Patent number: 8593766
    Abstract: A magneto-resistive effect (MR) element includes first and second magnetic layers in which a relative angle formed by magnetization directions changes responsive to an external magnetic field, and a spacer layer positioned between the first and second magnetic layers. The first magnetic layer is positioned closer to a substrate above which the MR element is formed than the second magnetic layer. The spacer layer includes copper and metal intermediate layers and a main spacer layer composed primarily of gallium oxide. The copper and metal intermediate layers are positioned between the main spacer and first magnetic layers. The metal intermediate layer is positioned between the copper and main spacer layers. The metal intermediate layer is composed primarily of at least one from a group of one of magnesium and at least partially oxidized magnesium, and one of aluminum and at least partially oxidized aluminum.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: November 26, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tsutomu Chou, Hironobu Matsuzawa, Hayato Koike
  • Patent number: 8582252
    Abstract: A magnetic sensor includes a magnetic layer comprising magnetic material and a grain refining agent. The magnetic layer having a grain-refined magnetic layer surface. A layer adjacent the magnetic layer has a layer surface that conforms to the grain-refined magnetic layer surface.
    Type: Grant
    Filed: November 2, 2005
    Date of Patent: November 12, 2013
    Assignee: Seagate Technology LLC
    Inventors: Brian William Karr, Eric Walter Singleton, Qing He
  • Patent number: 8582225
    Abstract: A microwave-assisted magnetic recording head includes: a main magnetic pole that generates a recording magnetic field to be recorded on a magnetic recording medium; a shield; and an oscillator that is provided between the main magnetic pole and the shield and generates a microwave magnetic field. The microwave-assisted magnetic recording head is provided with a thermal expansion device for adjusting a relative position between the oscillator and the main magnetic pole so as to be able to independently adjust a recording magnetic field from the main magnetic pole and a microwave magnetic field from the oscillator.
    Type: Grant
    Filed: February 1, 2011
    Date of Patent: November 12, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Masato Shiimoto, Masukazu Igarashi, Masaru Furukawa
  • Patent number: 8576519
    Abstract: A current-perpendicular-to-the-plane magnetoresistive sensor has magnetic damping material located adjacent either or both of the sensor side edges and back edge to reduce the effect of spin transfer torque. The damping material may be Pt, Pd, Os, or a rare earth metal from the 15 lanthanoid elements. The damping material may be an ultrathin layer in contact with the sensor edges. An insulating layer is deposited on the damping layer and isolates the sensor's ferromagnetic biasing layer from the damping layer. Instead of being a separate layer, the damping material may be formed adjacent the sensor edges by being incorporated into the material of the insulating layer.
    Type: Grant
    Filed: October 11, 2012
    Date of Patent: November 5, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Matthew J. Carey, Jeffrey R. Childress, Young-suk Choi, John Creighton Read
  • Patent number: 8558333
    Abstract: A method for manipulating domain pinning and reversal in a ferromagnetic material comprises applying an external magnetic field to a uniaxial ferromagnetic material comprising a plurality of magnetic domains, where each domain has an easy axis oriented along a predetermined direction. The external magnetic field is applied transverse to the predetermined direction and at a predetermined temperature. The strength of the magnetic field is varied at the predetermined temperature, thereby isothermally regulating pinning of the domains. A magnetic storage device for controlling domain dynamics includes a magnetic hard disk comprising a uniaxial ferromagnetic material, a magnetic recording head including a first magnet, and a second magnet. The ferromagnetic material includes a plurality of magnetic domains each having an easy axis oriented along a predetermined direction.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: October 15, 2013
    Assignees: The University of Chicago, UCL Business PLC
    Inventors: Daniel M. Silevitch, Thomas F. Rosenbaum, Gabriel Aeppli
  • Publication number: 20130242435
    Abstract: According to one embodiment, a magneto-resistance effect element includes: a first electrode; a second electrode; a first magnetic layer provided between the first and the second electrodes; a second magnetic layer provided between the first magnetic layer and the second electrode; and an oxide layer of a metal oxide provided between the first magnetic layer and the second magnetic layer. The oxide layer includes wustite crystal grains of a wustite structure with a (1 1 1) plane orientation containing iron. A lattice spacing of a (1 1 1) plane of the wustite crystal grains is not less than 0.253 nanometers and not more than 0.275 nanometers.
    Type: Application
    Filed: December 27, 2012
    Publication date: September 19, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko FUJI, Michiko Hara, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8525602
    Abstract: A magnetic device is provided in one example that comprises a free layer having a magnetic anisotropy. The magnetic anisotropy is at least partially non-uniform. The magnetic device further comprises an antiferromagnetic layer adjacent to and weakly exchange coupled with the free layer, wherein the weak exchange coupling reduces the non-uniformity of the magnetic anisotropy of the free layer.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: September 3, 2013
    Assignee: Honeywell International Inc.
    Inventor: Romney R. Katti
  • Patent number: 8518562
    Abstract: A magnetic storage device stable in write characteristic is provided. A first nonmagnetic film is provided over a recording layer. A first ferromagnetic film is provided over the first nonmagnetic film and has a first magnetization and a first film thickness. A second nonmagnetic film is provided over the first ferromagnetic film. A second ferromagnetic film is provided over the second nonmagnetic film, is coupled in antiparallel with the first ferromagnetic film, and has a second magnetization and a second film thickness. An antiferromagnetic film is provided over the second ferromagnetic film. The sum of the product of the first magnetization and the first film thickness and the product of the second magnetization and the second film thickness is smaller than the product of the magnetization of the recording layer and the film thickness of the recording layer.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: August 27, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Takashi Takenaga, Takeharu Kuroiwa, Hiroshi Takada, Ryoji Matsuda, Yosuke Takeuchi
  • Patent number: 8513751
    Abstract: A memory includes a semiconductor substrate. Magnetic tunnel junction elements are provided above the semiconductor substrate. Each of the magnetic tunnel junction elements stores data by a change in a resistance state, and the data is rewritable by a current. Cell transistors are provided on the semiconductor substrate. Each of the cell transistors is in a conductive state when the current is applied to the corresponding magnetic tunnel junction element. Gate electrodes are included in the respective cell transistors. Each of the gate electrodes controls the conductive state of the corresponding cell transistor. In active areas, the cell transistors are provided, and the active areas extend in an extending direction of intersecting the gate electrodes at an angle of (90-a tan(?)) degrees.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: August 20, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoshiaki Asao
  • Patent number: 8491799
    Abstract: A method for forming a magnetic tunnel junction cell includes forming a pinning layer, a pinned layer, a dielectric layer and a free layer over a first electrode, forming a second electrode on the free layer, etching the free layer and the dielectric layer using the second electrode as an etch barrier to form a first pattern, forming a prevention layer on a sidewall of the first pattern, and etching the pinned layer and the pinning layer using the second electrode and the prevention layer as an etch barrier to form a second pattern.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: July 23, 2013
    Assignee: Hynix Semiconductor Inc.
    Inventor: Jin-Ki Jung
  • Patent number: 8476724
    Abstract: A spin wave device comprises a metal layer, a pinned layer, a nonmagnetic layer, a free layer, an antiferromagnetic layer, a first electrode, a first insulator layer, and a second electrode. The pinned layer has a magnetization whose direction is fixed. The free layer has a magnetization whose direction is variable.
    Type: Grant
    Filed: September 12, 2011
    Date of Patent: July 2, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsuyoshi Kondo, Hirofumi Morise, Shiho Nakamura
  • Patent number: 8472149
    Abstract: The invention provides a giant magneto-resistive effect device of the CPP (current perpendicular to plane) structure (CPP-GMR device) comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked together with said spacer layer sandwiched between them, with a sense current passed in the stacking direction, wherein the first ferromagnetic layer and the second ferromagnetic layer function such that the angle made between the directions of magnetizations of both layers change relatively depending on an external magnetic field, said spacer layer contains a semiconductor oxide layer, and a nitrogen element-interface protective layer is provided at a position where the semiconductor oxide layer forming the whole or a part of said spacer layer contacts an insulating layer.
    Type: Grant
    Filed: October 1, 2007
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Daisuke Miyauchi, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Takahiko Machita
  • Patent number: 8472150
    Abstract: A giant magneto-resistive effect device (CPP-GMR device) having the CPP (current perpendicular to plane) structure comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked one upon another with the spacer layer interposed between them, with a sense current applied in a stacking direction, wherein the spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each made of a nonmagnetic metal material, and a semiconductor oxide layer interposed between the first nonmagnetic metal layer and the second nonmagnetic metal layer, the semiconductor oxide layer that forms a part of the spacer layer contains zinc oxide as its main component wherein the main component zinc oxide contains an additive metal, and the additive metal is less likely to be oxidized than zinc.
    Type: Grant
    Filed: January 3, 2008
    Date of Patent: June 25, 2013
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Kei Hirata, Koji Shimazawa, Shinji Hara
  • Patent number: 8449995
    Abstract: A protecting coating for a copper substrate is disclosed. The coating comprises seed layer comprising titanium ions that forms an “alloy-like” structure with the copper substrate. The coating further comprises a first layer of carbon disposed on the seed layer comprising titanium ions. A second layer comprising titanium is disposed on the first layer of carbon, and a second layer of carbon is disposed on the second layer comprising titanium.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: May 28, 2013
    Assignee: Seagate Technology LLC
    Inventors: Yongping Gong, Kristoffer Steven Scheponik
  • Patent number: 8432644
    Abstract: A spin torque oscillator device having a magnetic free layer with a magnetic anisotropy that has a component that is oriented perpendicular to a direction of an applied magnetic field. The spin torque oscillator device includes a magnetic reference layer, a magnetic free layer and a non-magnetic layer sandwiched there-between. A component of the magnetic anisotropy of the free layer can be oriented perpendicular to a magnetization of the reference layer, and this orientation relative to the magnetization of the reference layer can be either in lieu of or in addition to its orientation relative to the applied magnetic field. The magnetic anisotropy cants the magnetization of the free layer which would otherwise be oriented antiparallel with the magnetization of the reference layer. The magnetic anisotropy in the free layer improves performance of the spin torque sensor by reducing noise.
    Type: Grant
    Filed: September 16, 2010
    Date of Patent: April 30, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Patrick M. Braganca, Bruce A. Gurney
  • Patent number: 8411395
    Abstract: A method for driving a spin valve element, including passing driving current through the spin valve element to generate an oscillation signal, and performing amplitude modulation of the driving current at a frequency lower than the oscillation frequency of oscillation signals. This amplitude modulation can be ON-OFF modulation, and the interval ton in the conducting state of the ON-OFF modulation is made to satisfy the relation ton<D2/?, where ? is the thermal diffusivity of the heat diffusion portion, and D is the thickness of the heat diffusion portion.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: April 2, 2013
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Haruo Kawakami, Yasushi Ogimoto, Eiki Adachi