Super Lattice (e.g., Giant Magneto Resistance (gmr) Or Colossal Magneto Resistance (cmr), Etc.) Patents (Class 428/811.3)
  • Patent number: 11621392
    Abstract: A magnetoresistance effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, wherein at least one of the first ferromagnetic layer and the second ferromagnetic layer includes a first layer and a second layer in order from the side closer to the non-magnetic layer, the first layer contains a crystallized Co-based Heusler alloy, at least a part of the second layer is crystallized, the second layer contains a ferromagnetic element, boron element and an additive element, and the additive element is any element selected from a group consisting of Ti, V, Cr, Cu, Zn, Zr, Mo, Ru, Pd, Ta, W, Ir, Pt, and Au.
    Type: Grant
    Filed: September 21, 2021
    Date of Patent: April 4, 2023
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 11374170
    Abstract: Embodiments of the disclosure relate to methods for fabricating structures used in memory devices. More specifically, embodiments of the disclosure relate to methods for fabricating MTJ structures in memory devices. In one embodiment, the method includes forming a MTJ structure, depositing a encapsulating layer on a top and sides of the MTJ structure, depositing a dielectric material on the encapsulating layer, removing the dielectric material and the encapsulating layer disposed on the top of the MTJ structure by a chemical mechanical planarization (CMP) process to expose the top of the MTJ structure, and depositing a contact layer on the MTJ structure. The method utilizes a CMP process to expose the top of the MTJ structure instead of an etching process, which avoids damaging the MTJ structure and leads to improved electrical contact between the MTJ structure and the contact layer.
    Type: Grant
    Filed: September 25, 2018
    Date of Patent: June 28, 2022
    Assignee: APPLIED MATERIALS, INC.
    Inventors: Lin Xue, Jaesoo Ahn, Hsin-wei Tseng, Mahendra Pakala
  • Patent number: 11114225
    Abstract: A rare-earth thin film magnet is provided which includes Nd, Fe and B as essential components, characterized by including a Si substrate having an oxide film present on a surface thereof, a Nd base film formed as a first layer over the Si substrate, and a Nd—Fe—B film formed as a second layer on the first layer. The rare earth thin film magnet and a production process therefor provides a rare earth thin film magnet suffering neither film separation nor substrate breakage and having satisfactory magnetic properties even when the second layer has composition in the range of 0.120 ?Nd/(Nd+Fe)<0.150, which corresponds to a compositional range in the vicinity of a stoichiometric composition.
    Type: Grant
    Filed: February 28, 2017
    Date of Patent: September 7, 2021
    Assignee: JX NIPPON MINING & METALS CORPORATION
    Inventors: Masaki Nakano, Hirotoshi Fukunaga, Takeshi Yanai, Hironobu Sawatari
  • Patent number: 11074951
    Abstract: According to one embodiment, a magnetic memory device includes a magnetoresistive element including a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer. The first magnetic layer contains nickel (Ni), cobalt (Co), manganese (Mn) and gallium (Ga) and has a spin polarization less than 0.71.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: July 27, 2021
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventor: Tatsuya Kishi
  • Patent number: 10867625
    Abstract: A spin transfer torque (STT) device has a free ferromagnetic layer that includes a Heusler alloy layer and a template layer beneath and in contact with the Heusler alloy layer. The template layer may be a ferromagnetic alloy comprising one or more of Co, Ni and Fe and the element X, where X is selected from one or more of Ta, B, Hf, Zr, W, Nb and Mo. A CoFe nanolayer may be formed below and in contact with the template layer. The STT device may be a spin-torque oscillator (STO), like a STO incorporated into the write head of a magnetic recording disk drive. The STT device may also be a STT in-plane or perpendicular magnetic tunnel junction (MTJ) cell for magnetic random access memory (MRAM). The template layer reduces the critical current density of the STT device.
    Type: Grant
    Filed: February 27, 2020
    Date of Patent: December 15, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC
    Inventors: James Mac Freitag, Zheng Gao, Masahiko Hashimoto, Sangmun Oh, Hua Ai Zeng
  • Patent number: 10770213
    Abstract: The disclosed technology generally relates to a magnetoresistive device and more particularly to a magnetoresistive device comprising chromium. According to an aspect, a method of forming a magnetoresistive device comprises forming a magnetic tunnel junction (MTJ) structure over a substrate. The MTJ structure includes, in a bottom-up direction away from the substrate, a free layer, a tunnel barrier layer and a reference layer. The method additionally includes forming a pinning layer over the MTJ structure, wherein the pinning layer pins a magnetization direction of the reference layer. The method additionally includes forming capping layer comprising chromium (Cr) over the pinning layer. The method further includes annealing the capping layer under a condition sufficient to cause diffusion of Cr from the capping layer into at least the pinning layer. According to another aspect, a magnetoresistive device is formed according to the method.
    Type: Grant
    Filed: May 10, 2019
    Date of Patent: September 8, 2020
    Assignee: IMEC vzw
    Inventors: Johan Swerts, Sebastien Couet
  • Patent number: 10444303
    Abstract: A magnetic sensor including a first magneto resistive effect element located on a first surface of a substrate and having a sensitivity axis in a first direction that is one of in-plane directions of the first surface, a positioning soft magnetic body including a first most proximal portion of which a relative position with respect to the magneto resistive effect element is defined, and provided in a non-contact manner with respect to the first magneto resistive effect element, and a first soft magnetic body and a second soft magnetic body juxtaposed in the first direction and extending in a direction away from the first surface, and each of the first soft magnetic body and the second soft magnetic body is magnetically connected to the positioning soft magnetic body.
    Type: Grant
    Filed: February 15, 2017
    Date of Patent: October 15, 2019
    Assignee: Alps Alpine Co., Ltd.
    Inventors: Masayuki Obana, Hideto Ando, Yuki Imai, Kunio Yamanaka, Kyoko Hotta, Akira Miyatake, Toshihiro Kobayashi, Kenichiro Ikeda, Takafumi Noguchi
  • Patent number: 9128142
    Abstract: Provided is a spintronics device. The spintronics can include a ferromagnetic metal layer, a positive electrode disposed on a first surface portion of the ferromagnetic metal layer, and a negative electrode disposed on a second surface portion of the ferromagnetic metal.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: September 8, 2015
    Assignee: The Johns Hopkins University
    Inventors: Danru Qu, Bingfeng Miao, Chia-Ling Chien, Ssu-Yen Huang
  • Publication number: 20150064499
    Abstract: A method of producing a multilayer magnetoelectronic device and a related device. The method includes depositing a multilayer structure including at least two ferromagnetic layers disposed one on top of the other and each having a magnetic anisotropy with a corresponding magnetic moment. A magnetization curve is specified for the magnetoelectronic device. The number of ferromagnetic layers and, for each of the ferromagnetic layers, the magnetic moment and the magnetic hardness for obtaining the specified magnetization curve are determined. For each of the ferromagnetic layers a magnetic material, a thickness, an azimuthal angle and an angle of incidence are determined for obtaining the determined magnetic moment and magnetic hardness of the respective ferromagnetic layer. The multilayer structure is deposited using the determined material, thickness, azimuthal angle and angle of incidence for each of the ferromagnetic layers.
    Type: Application
    Filed: September 3, 2014
    Publication date: March 5, 2015
    Inventors: Kai Schlage, Denise Erb, Ralf Röhlsberger, Hans-Christian Wille, Daniel Schumacher, Lars Bocklage
  • Patent number: 8945730
    Abstract: A storage element including: a storage layer; a magnetization fixed layer; and an insulating layer, wherein by injecting spin-polarized electrons in a laminating direction of a layered structure that includes the storage layer, the insulating layer, and the magnetization fixed layer, the orientation of magnetization of the storage layer changes and recording of information is performed on the storage layer, and an Fe film and a film that includes Ni are formed in order from an interface side that is in contact with the insulating layer, and a graded composition distribution of Ni and Fe is formed after heating on at least one of the storage layer and the magnetization fixed layer.
    Type: Grant
    Filed: December 5, 2011
    Date of Patent: February 3, 2015
    Assignee: Sony Corporation
    Inventors: Hiroyuki Ohmori, Masanori Hosomi, Kazuhiro Bessho, Yutaka Higo, Kazutaka Yamane, Hiroyuki Uchida, Tetsuya Asayama
  • Publication number: 20150010780
    Abstract: A current-perpendicular-to-the-plane giant magnetoresistance (CPP-GMR) has a multilayer reference layer containing a Heusler alloy. The multilayer reference layer includes a crystalline non-Heusler alloy ferromagnetic layer on an antiferromagnetic layer, a Heusler alloy layer, and an intermediate crystalline non-Heusler alloy of the form CoFeX, where X is one or more of Ge, Al, Si and Ga, located between the non-Heusler alloy layer and the Heusler alloy layer. The CoFeX alloy layer has a composition (CoyFe(100-y))zX(100-z) where y is between about 10 and 90 atomic percent, and z is between about 50 and 90 atomic percent. The CoFeX alloy layer induces very strong pinning, which greatly lessens the likelihood of magnetic instability by the spin polarized electron flow from the free layer to the reference layer.
    Type: Application
    Filed: July 2, 2013
    Publication date: January 8, 2015
    Inventors: Matthew J. Carey, Jeffrey R. Childress, Young-suk Choi, John Creighton Read
  • Patent number: 8911888
    Abstract: Magnetic memories and methods are disclosed. A magnetic memory as described herein includes a plurality of stacked data storage layers to form a three-dimensional magnetic memory. The data storage layers are each formed from a multi-layer structure. At ambient temperatures, the multi-layer structures exhibit an antiparallel coupling state with a near zero net magnetic moment. At higher transition temperatures, the multi-layer structures transition from the antiparallel coupling state to a parallel coupling state with a net magnetic moment. At yet higher temperatures, the multi-layer structure transitions from the antiparallel coupling state to a receiving state where the coercivity of the multi-layer structures drops below a particular level so that magnetic fields from write elements or neighboring data storage layers may imprint data into the data storage layer.
    Type: Grant
    Filed: December 16, 2007
    Date of Patent: December 16, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Olav Hellwig, Bruce D. Terris, Jan-Ulrich Thiele
  • Publication number: 20140363699
    Abstract: A current-perpendicular-to-plane magnetoresistive read sensor includes a stack of layers extending along a stacking direction, and an edge surface parallel to the stacking direction that forms at least part of a bearing surface of the read sensor, the bearing surface designed to face a recording medium. The stack of layers includes a first contact layer, a ferromagnetic free layer whose magnetic orientation varies according to an applied magnetic field, above the first contact layer, a non-magnetic layer above the ferromagnetic layer, a ferromagnetic spin injection layer above the non-magnetic layer, and a second contact layer above the spin injection layer, such that a current can flow between the second contact layer and the first contact layer along a current-perpendicular-to-plane direction, parallel to the stacking direction. The stack of layers further includes a series of structures extending along a direction parallel to the bearing surface and perpendicular to the stacking direction.
    Type: Application
    Filed: June 2, 2014
    Publication date: December 11, 2014
    Applicant: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Simeon Furrer, Jens Jelitto, Mark A. Lantz
  • Publication number: 20140220385
    Abstract: The performance of an MR device has been improved by inserting one or more Magneto-Resistance Enhancing Layers (MRELs) into approximately the center of one or more of the magnetic layers such as an inner pinned (AP1) layer, spin injection layer (SIL), field generation layer (FGL), and a free layer. An MREL is a layer of a low band gap, high electron mobility semiconductor such as ZnO or a semimetal such as Bi. The MREL may further comprise a first conductive layer that contacts a bottom surface of the semiconductor or semimetal layer, and a second conductive layer that contacts a top surface of the semiconductor or semimetal layer.
    Type: Application
    Filed: April 4, 2014
    Publication date: August 7, 2014
    Applicant: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Publication number: 20140153139
    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: Application
    Filed: February 10, 2014
    Publication date: June 5, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akihiko TAKEO, Yoshihiko FUJI, Hiromi YUASA, Michiko HARA, Shuichi MURAKAMI, Hideaki FUKUZAWA
  • Publication number: 20140120374
    Abstract: A device including a magnetoresistive sensor; a top shield; and a bottom shield, wherein the magnetoresistive sensor is positioned between the top shield and the bottom shield, and wherein at least one of the bottom shield and the top shield include NiFeX, wherein X is chosen from Nb, Mo, Ta, or W.
    Type: Application
    Filed: November 1, 2012
    Publication date: May 1, 2014
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Meng Zhu, Michael C. Kautzky
  • 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
  • Publication number: 20130302649
    Abstract: [Problem to be Solved] To realize a spintronics device with high performance, it is an object of the present invention to provide a Co2Fe-based Heusler alloy having a spin polarization larger than 0.65, and a high performance spintronics devices using the same. [Solution] A Co2Fe(GaxGe1-x) Heusler alloy shows a spin polarization higher than 0.65 by a PCAR method in a region of 0.25<x<0.60 and it has a Curie temperature as high as 1288K. A CPP-GMR device that uses the Co2Fe(GaxGe1-x) Heusler alloy as an electrode exhibits the world's highest MR ratio, an STO device exhibits high output, and an NLSV device exhibits a high spin signal.
    Type: Application
    Filed: July 3, 2013
    Publication date: November 14, 2013
    Inventors: Yukiko Takahashi, Srinivasan Ananthakrishnan, Varaprasad Bollapragada, Rajanikanth Ammanabrolu, Jaivardhan Sinha, Masamitsu Hayashi, Takao Furubayashi, Shinya Kasai, Shigeyuki Hirayama, Seiji Mitani, Kazuhiro Hono
  • Publication number: 20130029182
    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: Application
    Filed: October 5, 2012
    Publication date: January 31, 2013
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Publication number: 20120295131
    Abstract: In some embodiments, a current perpendicular to the plane giant magneto-resistance (CPP GMR) read sensor may include a reference layer and/or a free layer that includes a plurality of sub-layers. For example, at least one of the reference layer or free layer may include a first ferromagnetic sub-layer, a second ferromagnetic sub-layer, and a Heusler alloy layer located between the first ferromagnetic sub-layer and the second ferromagnetic sub-layer. In some embodiments, a CPP GMR read sensor may include a current closed path (CCP) spacer layer between the reference layer and the free layer. The CCP spacer layer may include Ag and Al2O3. In further embodiments, a CPP GMR read sensor may include a Heusler alloy free layer, a Heusler alloy reference layer, and a CCP spacer layer.
    Type: Application
    Filed: July 24, 2012
    Publication date: November 22, 2012
    Applicant: Seagate Technology LLC
    Inventors: Qing He, Konstantin Nikolaev, Hao Meng, Yonghua Chen, Juren Ding
  • Patent number: 8274811
    Abstract: A spin transfer oscillator (STO) structure is disclosed that includes two assist layers with perpendicular magnetic anisotropy (PMA) to enable a field generation layer (FGL) to achieve an oscillation state at lower current density for MAMR applications. In one embodiment, the STO is formed between a main pole and write shield and the FGL has a synthetic anti-ferromagnetic structure. The STO configuration may be represented by seed layer/spin injection layer (SIL)/spacer/PMA layer 1/FGL/spacer/PMA layer 2/capping layer. The spacer may be Cu for giant magnetoresistive (GMR) devices or a metal oxide for tunneling magnetoresistive (TMR) devices. Alternatively, the FGL is a single ferromagnetic layer and the second PMA assist layer has a synthetic structure including two PMA layers with magnetic moment in opposite directions in a seed layer/SIL/spacer/PMA assist 1/FGL/spacer/PMA assist 2/capping layer configuration. SIL and PMA assist layers are laminates of (CoFe/Ni)x or the like.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: September 25, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Publication number: 20120164485
    Abstract: A current-perpendicular-to-plane (CPP) tunneling magnetoresistance (TMR) or giant magnetoresistance (GMR) read sensor with dual seed and cap layers for high-resolution magnetic recording is provided by the invention. The dual seed layers comprise a lower seed layer preferably formed of a nonmagnetic Pt film and an upper seed layer preferably formed of a nonmagnetic Ru film. The lower seed layer separates the upper seed layer from a buffer layer preferably formed of a ferromagnetic Co—Hf film, in order to minimize moment losses at its lower interface and thus define a sharp lower bound of a read gap. In addition, the lower seed layer facilitates the CPP read sensor to exhibit high pinning properties, while the upper seed layer facilitates the CPP read sensor to exhibit robust thermal properties.
    Type: Application
    Filed: December 22, 2010
    Publication date: June 28, 2012
    Applicant: Hitachi Global Strorage Technologies Netherland B.V.
    Inventor: Tsann Lin
  • 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: 8057925
    Abstract: A dual spin filter that minimizes spin-transfer magnetization switching current (Jc) while achieving a high dR/R in STT-RAM devices is disclosed. The bottom spin valve has a MgO tunnel barrier layer formed with a natural oxidation process to achieve low RA, a CoFe/Ru/CoFeB—CoFe pinned layer, and a CoFeB/FeSiO/CoFeB composite free layer with a middle nanocurrent channel (NCC) layer to minimize Jc0. The NCC layer may have be a composite wherein conductive M(Si) grains are magnetically coupled with adjacent ferromagnetic layers and are formed in an oxide, nitride, or oxynitride insulator matrix. The upper spin valve has a Cu spacer to lower the free layer damping constant. A high annealing temperature of 360° C. is used to increase the MR ratio above 100%. A Jc0 of less than 1×106 A/cm2 is expected based on quasistatic measurements of a MTJ with a similar MgO tunnel barrier and composite free layer.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: November 15, 2011
    Assignee: MagIC Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Publication number: 20110183158
    Abstract: A CPP-GMR spin valve having a CoFe/NiFe composite free layer is disclosed in which Fe content of the CoFe layer ranges from 20 to 70 atomic % and Ni content in the NiFe layer varies from 85 to 100 atomic % to maintain low Hc and ?S values. A higher than normal Fe content in the CoFe layer improves the MR ratio by ?16% compared with conventional CoFe/NiFe free layers in which the Fe content in CoFe is typically <20 atomic % and the Ni content in NiFe is <85 atomic %. The CPP-GMR performance may also be optimized by incorporating a confining current path layer in the copper spacer between the pinned layer and free layer. For a pinned layer with an AP2/Ru/AP1 configuration, the spin valve performance is further improved by an AP1 layer comprised of a lamination of CoFe and Cu layers as in [CoFe/Cu]2/CoFe.
    Type: Application
    Filed: April 4, 2011
    Publication date: July 28, 2011
    Inventors: Kunliang Zhang, Min Li, Yu-Hsia Chen, Chyu-Jiuh Torng
  • Publication number: 20110163739
    Abstract: Provided are a self-pinned spin valve magnetoresistance effect film, a magnetic sensor using the same, and a rotation angle detection device. The self-pinned spin valve magnetoresistance effect film has a strong coupling magnetic field in a pinned layer, a small reduction in the change in resistance, and superior resistance to magnetic fields without reducing the coercive force in a first ferromagnetic layer, which is a pinned layer in the film, even when exposed to a strong external magnetic field. By inserting a non-magnetic layer between a ground layer and a pinned layer to form the spin valve magnetoresistance effect film, the self-pinned spin valve magnetoresistance effect film having superior resistance to magnetic fields, a magnetic sensor using the same, and a rotation angle detection device are obtained.
    Type: Application
    Filed: August 10, 2009
    Publication date: July 7, 2011
    Applicant: HITACHI METALS, LTD.
    Inventors: Tomoki Ono, Yasunori Abe, Fumio Shirasaki
  • Patent number: 7897274
    Abstract: A magnetoresistive device includes a magnetization pinned layer, a magnetization free layer, a nonmagnetic intermediate layer formed between the magnetization pinned layer and the magnetization free layer, and electrodes allowing a sense current to flow in a direction substantially perpendicular to the plane of the stack including the magnetization pinned layer, the nonmagnetic intermediate layer and the magnetization free layer. At least one of the magnetization pinned layer and the magnetization free layer is substantially formed of a binary or ternary alloy represented by the formula FeaCobNic (where a+b+c=100 at %, and a?75 at %, b?75 at %, and c?63 at %), or formed of an alloy having a body-centered cubic crystal structure.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Masatoshi Yoshikawa, Yuzo Kamiguchi, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20100310903
    Abstract: The present invention provides an alloy film of Mn or its Fe—Mn is depositable on a metalized alumina ceramic (Al2O3-SiO3) substrate for hermetically sealed glass-metal fusion used for aircraft switch assemblies. The coefficient of thermal expansion of Fe—Mn alloys appear to be fairly low, nearer to that of glass. Fe—Mn alloy film is an alternative to Fe64—Ni36 alloy films (Invar) normally used for glass to glass fusion purposes. Fe—Mn alloy films is also depositable directly on bare Alumina (Al2O3) substrate with or without zincating pretreatment. Similarly bright, smooth coherent film of Mn—Au or Fe—Mn—Ni Au alloys is depositable from an aqueous solution of simple salt bath or on Cu substrate without the use of cyanide without bridging with zincate processes.
    Type: Application
    Filed: January 19, 2010
    Publication date: December 9, 2010
    Inventor: Bassey J. Udofot
  • Publication number: 20100188782
    Abstract: A magnetoresistive element includes: a detection surface that receives a magnetic field to be detected; a free layer made of a ferromagnetic material, having an end face located in the detection surface, and exhibiting a change in magnetization direction in response to the magnetic field to be detected; a pinned layer made of a ferromagnetic material, disposed away from the detection surface, and having a fixed magnetization direction; and a coupling portion made of a nonmagnetic material and coupling the free layer to the pinned layer. The coupling portion includes a nonmagnetic conductive layer that allows electrons to be conducted while conserving their spins.
    Type: Application
    Filed: January 28, 2009
    Publication date: July 29, 2010
    Applicant: TDK CORPORATION
    Inventor: Hiroshi Yamazaki
  • Patent number: 7684161
    Abstract: A synthetic antiferromagnet (SAF) structure includes a first ferromagnetic layer, a first insertion layer, a coupling layer, a second insertion layer, and a second ferromagnetic layer. The insertion layers comprise materials selected such that SAF exhibits reduced temperature dependence of antiferromagnetic coupling strength. The insertion layers may include CoFe or CoFeX alloys. The thickness of the insertion layers is selected such that they do not increase the uniaxial anisotropy or deteriorate any other properties.
    Type: Grant
    Filed: April 18, 2006
    Date of Patent: March 23, 2010
    Assignee: Everspin Technologies, Inc.
    Inventors: Srinivas V. Pietambaram, Renu W. Dave, Jon M. Slaughter, JiJun Sun
  • Publication number: 20090225635
    Abstract: A magnetic artificial superlattice is composed of laminated thin films including two or more kinds of magnetic flaky particles (magnetic titania nanosheets) obtained by exfoliation of a layer titanium oxide in which Ti atoms in the lattice have been substituted with magnetic elements.
    Type: Application
    Filed: December 13, 2006
    Publication date: September 10, 2009
    Inventors: Minoru Osada, Takayoshi Sasaki
  • Publication number: 20090176129
    Abstract: Embodiments of the present invention relate to a galvanomagnetic device for use as a magnetic sensor or magnetic memory device. In a particular embodiment, the galvanomagnetic device comprises a non-conductive substrate, a first magnetic layer having a magnetic anisotropy perpendicular to the surface thereof, and a ferromagnetic second magnetic layer formed on the first magnetic layer. On the second magnetic layer, current electrodes are disposed to pass a current between two points, and voltage electrodes are disposed to detect a Hall voltage between two points perpendicularly to the current flow direction.
    Type: Application
    Filed: December 24, 2008
    Publication date: July 9, 2009
    Inventors: Das Sarbanoo, Hiroyuki Suzuki, Takayoshi Ohtsu
  • Publication number: 20090161268
    Abstract: A method, apparatus, and article of manufacture for a current-perpendicular-to-plane (CPP) giant magnetoresistance (GMR) or a tunneling magnetoresistance (TMR) read sensor is proposed. The CPP read sensor comprises an amorphous ferromagnetic first seed layer, a polycrystalline nonmagnetic second seed layer, a nonmagnetic first cap layer, a nonmagnetic second cap layer, and a ferromagnetic third gap layer. A read gap is defined by a distance between the ferromagnetic first seed layer and the ferromagnetic third cap layer.
    Type: Application
    Filed: December 22, 2007
    Publication date: June 25, 2009
    Inventor: Tsann Lin
  • Publication number: 20090061258
    Abstract: A magnetic field detecting element comprises: a stack which includes first, second and third magnetic layers whose magnetization directions change in accordance with an external magnetic field, a first non-magnetic intermediate layer which is sandwiched between the first magnetic layer and the second magnetic layer, the first non-magnetic intermediate layer producing a magnetoresistance effect between the first magnetic layer and the second magnetic layer, and a second non-magnetic intermediate layer which is sandwiched between the second magnetic layer and the third magnetic layer, the second non-magnetic intermediate layer allowing the second magnetic layer and the third magnetic layer to be exchange-coupled such that magnetization directions thereof are anti-parallel to each other under no magnetic field, the stack being adapted such that sense current flows in a direction that is perpendicular to a film surface thereof; and a bias magnetic layer which is provided on a side of the stack, the side being opp
    Type: Application
    Filed: August 30, 2007
    Publication date: March 5, 2009
    Inventors: Tomohito MIZUNO, Yoshihiro TSUCHIYA, Shinji HARA, Koji SHIMAZAWA, Tsutomu CHOU
  • Patent number: 7390584
    Abstract: A ferromagnetic thin-film based magnetic device with internal film coupling compensation including a nonmagnetic material intermediate layer with an initial thin-film of an anisotropic ferromagnetic material on one side. A compensation thin-film of an anisotropic ferromagnetic material is provided on the opposite side with an antiparallel coupling layer thereon and a subsequent thin-film of an anisotropic ferromagnetic material on the antiparallel coupling layer with the compensation thin-film being less thick than the subsequent thin-film. A antiferromagnetic layer can be supported by the layers on either side of the intermediate layer.
    Type: Grant
    Filed: March 21, 2003
    Date of Patent: June 24, 2008
    Assignee: NVE Corporation
    Inventors: James M. Daughton, Dexin Wang
  • Publication number: 20080008909
    Abstract: A 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 means of 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: Application
    Filed: May 23, 2007
    Publication date: January 10, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 7163755
    Abstract: The present invention provides a vertical current-type magneto-resistive element. The element includes an intermediate layer and a pair of magnetic layers sandwiching the intermediate layer, and at least one of a free magnetic layer and a pinned magnetic layer is a multilayer film including at least one non-magnetic layer and magnetic layers sandwiching the non-magnetic layer. The element area defined by the area of the intermediate layer through which current flows perpendicular to the film is not larger than 1000 ?m2.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: January 16, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masayoshi Hiramoto, Nozomu Matukawa, Akihiro Odagawa, Kenji Iijima, Hiroshi Sakakima
  • Patent number: 7092222
    Abstract: A seed layer having a chromium content in the range of 35 to 60 atomic percent and a thickness of 10 to 200 ? is deposited to have a single phase of the face-centered cubic structure by optimizing the sputtering conditions, etc. The surface of the seed layer maintaining the face-centered cubic structure exhibits improved wettability, and the rate of change in resistance ?R/R can thereby be improved.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: August 15, 2006
    Assignee: Alps Electric Co., Ltd.
    Inventors: Naoya Hasegawa, Masamichi Saito
  • Patent number: 7005201
    Abstract: In a magnetic detecting element, second ferromagnetic layers are deposited on respective second antiferromagnetic layers. The magnetization direction of the second ferromagnetic layers is antiparallel to that of first ferromagnetic layers. A static magnetic field generated by a surface magnetic charge at the internal side surfaces of the first ferromagnetic layers is absorbed by the second ferromagnetic layers. Thus, it becomes hard that the static magnetic field from the first ferromagnetic layers enters the central portion of a free magnetic layer. Consequently, the central portion of the free magnetic layer can maintain its single magnetic domain state, and, thus, the hysteresis can be reduced and the Barkhausen noise is suppressed.
    Type: Grant
    Filed: September 5, 2003
    Date of Patent: February 28, 2006
    Assignee: Alps Electric Co., Ltd.
    Inventors: Naoya Hasegawa, Eiji Umetsu