Having One Film Pinned (e.g., Spin Valve) Patents (Class 360/324.1)
  • Patent number: 7964924
    Abstract: A magneto-resistance effect device (1) includes a semiconductor region (2) having a surface provided with a plurality of isolated metal micro-particles (3) of not more than 100 ?m disposed at intervals of not more than 1 ?m, a semiconductor or half-metal cap layer (4) for covering the semiconductor region and a plurality of electrodes (5) disposed on a surface of the cap layer and separated from each other. The device exhibits a high magneto-resistance effect at room temperature, is highly sensible to a magnetic field and can be produced through a simple manufacturing process. The device is formed of a magneto-resistant material easy to match a semiconductor fabrication process. A magnetic field sensor using the device (1) has various excellent characteristics.
    Type: Grant
    Filed: May 24, 2002
    Date of Patent: June 21, 2011
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Hiroyuki Akinaga, Masaharu Oshima, Masaki Mizuguchi
  • Patent number: 7957106
    Abstract: Magnetoresistive (MR) read elements and associated methods of fabrication are disclosed. A free layer and/or a pinned layer of an MR read element are formed from a magnetic material such as Co2?x?yMn1+xAl1+y, Co2?x?yMn1+xSi1+y, Co2?x?yMn1+xGe1+y, and Co2?x?yFe1+xSi1+y, where x and y are selected to create an off-stoichiometric alloy having a crystalline structure that is chemically disordered. The chemically disordered magnetic material has a lower spin-polarization than a Heusler alloy, but still exhibits acceptable GMR amplitudes and low spin-torque noise.
    Type: Grant
    Filed: April 30, 2007
    Date of Patent: June 7, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Matthew J. Carey, Jeffrey R. Childress, Stefan Maat
  • Patent number: 7957108
    Abstract: An MR element includes a free layer having a direction of magnetization that changes in response to an external magnetic field, a pinned layer having a fixed direction of magnetization, and a spacer layer disposed between these layers. The spacer layer includes a first region, a second region and a third region that are each in the form of a layer and that are arranged in a direction intersecting the plane of each of the foregoing layers. The second region is sandwiched between the first region and the third region. The first region and the third region are each composed of an oxide semiconductor, and the second region includes at least a nonmagnetic conductor phase.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: June 7, 2011
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Tomohito Mizuno
  • Patent number: 7952839
    Abstract: An MR element includes a first ferromagnetic layer, a second ferromagnetic layer, a spacer layer disposed between the first and second ferromagnetic layers; and an antiferromagnetic layer disposed on a side of the first ferromagnetic layer farther from the spacer layer. The antiferromagnetic layer is disposed away from a detection surface. The first ferromagnetic layer includes: a first portion having an end face located in the detection surface and a rear end opposite to the end face; and a second portion located away from the detection surface and connected to the rear end of the first portion. The first portion has a first surface touching the spacer layer, and a second surface that is opposite to the first surface and that does not touch the antiferromagnetic layer. The second portion has a third surface touching the antiferromagnetic layer, and a fourth surface opposite to the third surface.
    Type: Grant
    Filed: January 28, 2008
    Date of Patent: May 31, 2011
    Assignee: TDK Corporation
    Inventors: Hiroshi Yamazaki, Naoki Ohta
  • Patent number: 7950135
    Abstract: A manufacturing method of an MR element in which current flows in a direction perpendicular to layer planes, includes a step of forming on a lower electrode layer an MR multi-layered structure with side surfaces substantially perpendicular to the layer lamination plane, a step of forming a first insulation layer on at least the side surfaces of the formed MR multi-layered structure, a step of forming a second insulation layer and a magnetic domain control bias layer on the lower electrode layer, and a step of forming an upper electrode layer on the MR multi-layered structure and the magnetic domain control bias layer.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: May 31, 2011
    Assignee: TDK Corporation
    Inventors: Takeo Kagami, Takayasu Kanaya
  • Patent number: 7948718
    Abstract: An MR element incorporates: a nonmagnetic conductive layer having two surfaces facing toward opposite directions; a free layer disposed adjacent to one of the surfaces of the nonmagnetic conductive layer, wherein the direction of magnetization in the free layer changes in response to an external magnetic field; and a pinned layer disposed adjacent to the other of the surfaces of the nonmagnetic conductive layer, wherein the direction of magnetization in the pinned layer is fixed to the direction orthogonal to the air bearing surface. The MR element does not include any layer provided for fixing the direction of magnetization in the pinned layer. The pinned layer incorporates a ferromagnetic layer made of a ferromagnetic material having a positive magnetostriction constant. A bottom shield gap film and a top shield gap film disposed adjacent to the MR element each have a compressive stress of 600 MPa or greater.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: May 24, 2011
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Koji Shimazawa
  • Patent number: 7944651
    Abstract: Embodiments of the present invention help to prevent a reduction in the bias magnetic field of a current perpendicular to the plane-type (CPP-type) magnetoresistive effect head, thus suppressing a reduction in read output. According to one embodiment, a CPP-type magnetoresistive effect film is formed on top of a lower magnetic shield. A refill insulation film and a magnetic domain control layer are formed on both sides of an intermediate layer and a free layer of the CPP-type magnetoresistive effect film. A side wall protection film is formed on a side wall of the refill insulation film and on top of the free layer so as to define the height of the magnetic domain control layer. To increase the film thickness of the magnetic domain control layer, the magnetic domain control layer and the refill insulation film are higher than the top surface of the free layer.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: May 17, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masahiro Ousugi, Kouji Okazaki, Satoru Okamoto, Katsuro Watanabe
  • Patent number: 7944650
    Abstract: An MR element includes an MR stack including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer disposed between the first and the second ferromagnetic layer. The MR stack has an outer surface, and the spacer layer has a periphery located in the outer surface of the MR stack. The magnetoresistive element further includes a layered film that touches the periphery of the spacer layer. The spacer layer includes a semiconductor layer formed using an oxide semiconductor as a material. The layered film includes a first layer, a second layer, and a third layer stacked in this order. The first layer is formed of the same material as the semiconductor layer, and touches the periphery of the spacer layer. The second layer is a metal layer that forms a Schottky barrier at the interface between the first layer and the second layer. The third layer is an insulating layer.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: May 17, 2011
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Koji Shimazawa, Tomohito Mizuno, Shinji Hara, Daisuke Miyauchi, Takahiko Machita
  • Patent number: 7936539
    Abstract: A bottom spin-valve GMR sensor has been fabricated that has ultra-thin layers of high density and smoothness. In addition, these layers are inherently furnished with sub-monolayer thick oxygen surfactant layers. The sensor is fabricated using a method in which the layers are sputtered in a mixture of Ar and O2. A particularly novel feature of the method is the use of a sputtering chamber with an ultra-low base pressure and correspondingly ultra-low pressure mixtures of Ar and O2 sputtering gas (<0.5 millitorr) in which the admixed oxygen has a partial pressure of less than 5×10?9 torr.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: May 3, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Patent number: 7929257
    Abstract: A magnetic thin film has a pinned layer whose magnetization direction is fixed with respect to an external magnetic field, a free layer whose magnetization direction is changed according to the external magnetic field, and a spacer layer which is sandwiched between said pinned layer and said free layer. Sense current is configured to flow in a direction that is perpendicular to film surfaces of said pinned layer, said spacer layer, and said free layer. Said spacer layer has a CuZn metal alloy which includes an oxide region, said oxide region consisting of an oxide of any of Al, Si, Cr, Ti, Hf, Zr, Zn, and Mg.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: April 19, 2011
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Tomohito Mizuno, Yoshihiro Tsuchiya, Daisuke Miyauchi, Shinji Hara
  • Publication number: 20110085258
    Abstract: An information storage device includes a magnetic track and a magnetic domain wall moving unit. The magnetic track has a plurality of magnetic domains and a magnetic domain wall between each pair of adjacent magnetic domains. The magnetic domain wall moving unit is configured to move at least the magnetic domain wall. The information storage device further includes a magneto-resistive device configured to read information recorded on the magnetic track. The magneto-resistive device includes a pinned layer, a free layer and a separation layer arranged there between. The pinned layer has a fixed magnetization direction. The free layer is disposed between the pinned layer and the magnetic track, and has a magnetization easy axis, which is non-parallel to the magnetization direction of the pinned layer.
    Type: Application
    Filed: June 22, 2010
    Publication date: April 14, 2011
    Inventors: Ji-young Bae, Sung-chul Lee, Sun-ae Seo, Young-jin Cho, Ung-hwan Pi, Jin-seong Heo
  • Patent number: 7919139
    Abstract: CPP magnetic read head designs have been improved by increasing the length of the AFM layer relative to that of both the free and spacer layers. The length of the pinned layer is also increased, but by a lesser amount, an abutting conductive layer being inserted to fill the remaining space over the AFM layer. The extended pinned layer increases the probability of spin interaction while the added conducting layer serves to divert sensor current away from the bottom magnetic shield which now is no longer needed for use as a lead.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: April 5, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Charles C. Lin, Min Li
  • Patent number: 7920362
    Abstract: A giant magneto-resistive effect device having a CPP structure including a spacer layer, and a fixed magnetization layer and a free layer stacked one upon another with said spacer layer interposed between them. The free layer functions such that its magnetization direction changes depending on an external magnetic field. The spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each formed of a nonmagnetic metal material. A semiconductor oxide layer is interposed between them. The semiconductor oxide layer forming a part of the spacer layer comprises zinc oxide as a main ingredient.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: April 5, 2011
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Kei Hirata, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Patent number: 7920361
    Abstract: It is made possible to provide a magnetoresistive effect element that can reverse magnetization direction with a low current, having low areal resistance (RA) and a high TMR ratio. A magnetoresistive effect element includes: a film stack that includes a magnetization free layer including a magnetic layer in which magnetization direction is changeable, a magnetization pinned layer including a magnetic layer in which magnetization direction is pinned, and an intermediate layer provided between the magnetization free layer and the magnetization pinned layer, the intermediate layer being an oxide containing boron (B) and an element selected from the group consisting of Ca, Mg, Sr, Ba, Ti, and Sc. Current is applied bidirectionally between the magnetization pinned layer and the magnetization free layer through the intermediate layer, so that the magnetization of the magnetization free layer is reversible.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: April 5, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Yoshikawa, Tadashi Kai, Toshihiko Nagase, Eiji Kitagawa, Tatsuya Kishi, Hiroaki Yoda
  • Patent number: 7916432
    Abstract: The thin-film patterning method for a magnetoresistive device comprises forming a functional layer on a substrate; forming a first mask layer above the functional layer; forming a patterned resist on the first mask layer; etching the first mask layer by using the resist; removing the resist; forming a second mask layer by atomic layer deposition, the second mask layer covering a step defined by an edge of the first mask layer; dry-etching the second mask layer in a thickness direction of the substrate so as to leave the second mask layer on a side face of the step; removing the first mask layer so as to expose the functional layer under the first mask; and dry-etching the functional layer by using the second mask layer.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: March 29, 2011
    Assignee: TDK Corporation
    Inventors: Naoki Ohta, Kazuki Sato, Kosuke Tanaka
  • Patent number: 7916431
    Abstract: An MR element includes a stack of layers including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer disposed between the first and the second ferromagnetic layer. The stack of layers has an outer surface, and the spacer layer has a periphery located in the outer surface of the stack of layers. The magnetoresistive element further includes an insulating film that touches the periphery of the spacer layer. The spacer layer includes a layer made of an oxide semiconductor composed of an oxide of a first metal. The insulating film includes a contact film that touches the periphery of the spacer layer and that is made of an oxide of a second metal having a Pauling electronegativity lower than that of the first metal by 0.1 or more.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: March 29, 2011
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Shinji Hara, Daisuke Miyauchi, Takahiko Machita
  • Patent number: 7911744
    Abstract: The invention provides a giant magneto-resistive effect device (CPP-GMR device) having a CPP (current perpendicular to plane) structure comprising a multilayer device assembly comprising a fixed magnetization layer, a spacer layer, a free layer and a cap layer stacked one upon another in order, with a sense current applied in a stacking direction of the multilayer device assembly. In the rear of the multilayer device assembly, there is a refilled insulation layer formed, which is in contact with the rear end face of the multilayer device assembly and extends rearward, wherein the uppermost position P of the refilled insulation layer that is in contact with the rear end face of said multilayer device assembly lies at a rear end face of the cap layer and is set in such a way as to satisfy a relation: 0.2?(T2/T1)<1 where T1 is the thickness of the cap layer, and T2 is the absolute value of a distance from the uppermost portion of the cap layer down to the position P as viewed in a thickness direction.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: March 22, 2011
    Assignee: TDK Corporation
    Inventors: Takahiko Machita, Daisuke Miyauchi
  • Patent number: 7900342
    Abstract: Magnetoresistance sensors with magnetic pinned layers that are pinned by anisotropic etch induced magnetic anisotropies and methods for fabricating the magnetoresistance sensors are provided. The method comprises forming a seed layer structure. The seed layer is etched to form an anisotropic etch along a top surface of the seed layer. A magnetic pinned layer is formed on the top surface of the seed layer structure. The anisotropic etch on the top surface of the seed layer structure induces a magnetic anisotropy in the magnetic pinned layer, which pins the magnetization of the magnetic pinned layer structure.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: March 8, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: James M. Freitag, Mustafa M. Pinarbasi
  • Patent number: 7898774
    Abstract: A spin valve type magnetoresistive effect element for vertical electric conduction includes a magnetoresistive effect film in which a resistance adjustment layer made of a material containing conductive carriers not more than 1022/cm3 is inserted. Thus the resistance value of a portion in change of spin-relied conduction is raised to an adequate value, thereby to increase the resistance variable amount.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7894168
    Abstract: The invention provides a thin-film magnetic head having a magneto-resistive effect device of the CPP (current perpendicular to plane) structure comprising a multilayer film in which a fixed magnetization layer, a nonmagnetic layer and a free layer are stacked together in order. The fixed magnetization layer, nonmagnetic layer and free layer extend away from an air bearing surface that is a plane in opposition to a medium, the length of the fixed magnetization layer in a depth direction normal to said air bearing surface is greater than the length of the free layer in the depth direction. A shunt layer for shunting the sense current is located at a farther distance in the depth direction than the free layer, and the shunt layer is separated from the free layer by a constant gap in the depth direction.
    Type: Grant
    Filed: August 28, 2007
    Date of Patent: February 22, 2011
    Assignee: TDK Corporation
    Inventors: Hiroshi Kiyono, Tetsuya Kuwashima
  • Patent number: 7891081
    Abstract: A process is described for the fabrication of a magnetic read head in which contact between the pinned layer and the AFM is limited to their edges. The principal steps are to deposit an antiferromagnetic layer and to then pattern it into a pair of antiferromagnetic layers separated by no more than about 2 microns. A layer of magnetic material that lies between, and is in contact with, said antiferromagnetic layers is then deposited, following which the layer of magnetic material is magnetized.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: February 22, 2011
    Assignee: Headway Technologies, Inc.
    Inventor: Glen Garfunkel
  • Patent number: 7880209
    Abstract: A free ferromagnetic data storage layer of an MRAM cell is coupled to a free ferromagnetic stabilization layer, which stabilization layer is directly electrically coupled to a contact electrode, on one side, and is separated from the free ferromagnetic data storage layer, on an opposite side, by a spacer layer. The spacer layer provides for the coupling between the two free layers, which coupling is one of: a ferromagnetic coupling and an antiferromagnetic coupling.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: February 1, 2011
    Assignee: Seagate Technology LLC
    Inventors: Haiwen Xi, Kaizhong Gao, Dimitar V. Dimitrov, Song S. Xue
  • Patent number: 7881022
    Abstract: Embodiments in accordance with the present invention provide a sensor to produce high output with a small track width. Particular embodiments include forming a magnetoresistive sensor of a read head to be substantially vertical in its upper portion and gently upwardly convexly curved in its lower portion.
    Type: Grant
    Filed: April 17, 2007
    Date of Patent: February 1, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hisako Takei, Nobuo Yoshida, Hiroyuki Hoshiya, Taku Shintani
  • Patent number: 7864490
    Abstract: The series resistance of a CPP GMR stack can be reduced by shaping it into a small upper, on a somewhat larger, lower part. Because of the sub-micron dimensions involved, good alignment between these is normally difficult to achieve. The present invention discloses a self-alignment process based on first laying down a mask that will determine the shape of the top part. Ion beam etching is then initiated, the ion beam being initially applied from one side only at an angle to the surface normal. During etching, all material on the near side of the mask gets etched but, on the far side, only material that is outside the mask's shadow gets removed so, depending on the beam's angle, the size of the lower part is controlled and the upper part is precisely centrally aligned above it.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: January 4, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Jeiwei Chang, Stuart Kao, Chao Peng Chen, Chunping Luo, Kochan Ju, Min Li
  • Publication number: 20100328822
    Abstract: A method and system for providing a magnetic recording transducer is described. The method and system include providing a pinned layer for a magnetic element. In one aspect, a portion of a tunneling barrier layer for the magnetic element is provided. The magnetic recording transducer annealed is after the portion of the tunneling barrier layer is provided. The annealing is at a temperature higher than room temperature. A remaining portion of the tunneling barrier layer is provided after the annealing. In another aspect, the magnetic transducer is transferred to a high vacuum annealing apparatus before annealing the magnetic transducer. In this aspect, the magnetic transducer may be annealed before any portion of the tunneling barrier is provided or after at least a portion of the tunneling barrier is provided. The annealing is performed in the high vacuum annealing apparatus. A free layer for the magnetic element is also provided.
    Type: Application
    Filed: June 26, 2009
    Publication date: December 30, 2010
    Applicant: WESTERN DIGITAL (FREMONT), LLC
    Inventors: CHANDO PARK, QUNWEN LENG, MAHENDRA PAKALA
  • Patent number: 7859799
    Abstract: Embodiments in accordance with the present invention reduce the influence of etching damage at junction edge of a magnetoresistive film in the sensor height direction, lower the deterioration of dielectric breakdown voltage between an upper magnetic shield layer and a lower magnetic shield layer and instability of reproducing property resulting from shield process, and maintain electrostatic capacity to a small value in a CPP magnetoresistive head. In an embodiment of a magnetoresistive head of the present invention, length in the sensor height direction of bottom surface of a pinning layer is longer than the length in the sensor height direction of bottom surface of a first ferromagnetic layer.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: December 28, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Katsuro Watanabe, Taku Shintani, Kazuhiro Ueda, Masahiro Osugi
  • Patent number: 7859798
    Abstract: A magnetic thin film has: a pinned layer whose magnetization direction is fixed with respect to an external magnetic field; a free layer whose magnetization direction is changed in accordance with the external magnetic field; and a non-magnetic spacer layer that is sandwiched between said the pinned layer and the free layer, wherein sense current is configured to flow in a direction that is perpendicular to film surfaces of the pinned layer, the non-magnetic spacer layer, and the free layer. The non-magnetic spacer layer has a first layer which includes SnO2, and a pair of second layers which are provided to sandwich the first layer, the second layers being made of a material which exhibits a higher corrosion potential than Sn.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: December 28, 2010
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Patent number: 7855859
    Abstract: In an MR element, first and second ferromagnetic layers are antiferromagnetically coupled to each other through a spacer layer, and have magnetizations that are in opposite directions when no external magnetic field is applied thereto and that change directions in response to an external magnetic field. The spacer layer and the second ferromagnetic layer are stacked in this order on the first ferromagnetic layer. The first ferromagnetic layer includes a plurality of ferromagnetic material layers stacked, and an insertion layer made of a nonmagnetic material and inserted between respective two of the ferromagnetic material layers that are adjacent to each other along the direction in which the layers are stacked. The ferromagnetic material layers and the spacer layer each include a component whose crystal structure is a face-centered cubic structure.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: December 21, 2010
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Tsuyoshi Ichiki, Toshiyuki Ayukawa
  • Patent number: 7842334
    Abstract: A magnetic sensor includes a single substrate, a conventional GMR element formed of a spin-valve film including a single-layer-pinned fixed magnetization layer, and a SAF element formed of a synthetic spin-valve film including a plural-layer-pinned fixed magnetization layer. When the spin-valve film intended to act as the conventional GMR element and the synthetic spin-valve film intended to act as the SAF element are subjected to the application of a magnetic field oriented in a single direction at a high temperature, they become giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other. Since films intended to act as the conventional GMR element and the SAF element can be disposed close to each other, the magnetic sensor which has giant magnetoresistive elements whose magnetic-field-detecting directions are antiparallel to each other can be small.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: November 30, 2010
    Assignee: Yamaha Corporation
    Inventors: Yukio Wakui, Masayoshi Omura
  • Patent number: 7843669
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of nitride, oxinitride, phosphide, and fluoride.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: November 30, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7826180
    Abstract: The invention provides a giant magneto-resistive effect device (CPP-GMR device) having a CPP (current perpendicular to plane) structure comprising a spacer layer, and a fixed magnetized layer and a free layer stacked one upon another with said spacer layer interposed between them, with a sense current applied in a stacking direction, wherein the free layer functions such that the direction of magnetization changes depending on an external magnetic field, and the spacer layer comprises a first and a second nonmagnetic metal layer, each formed of a nonmagnetic metal material, and a semiconductor oxide layer interposed between the first and the second nonmagnetic metal layer, wherein the semiconductor oxide layer that forms a part of the spacer layer is made of zinc oxide, tin oxide, indium oxide, and indium tin oxide (ITO), the first nonmagnetic metal layer is made of Cu, and the second nonmagnetic metal layer is substantially made of Zn.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: November 2, 2010
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Tomohito Mizuno, Shinji Hara
  • Patent number: 7826181
    Abstract: A magnetic element having a ferromagnetic pinned layer, a ferromagnetic free layer, a non-magnetic spacer layer therebetween, and a porous non-electrically conducting current confinement layer between the free layer and the pinned layer. The current confinement layer forms an interface either between the free layer and the non-magnetic spacer layer or the pinned layer and the non-magnetic spacer layer.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: November 2, 2010
    Assignee: Seagate Technology LLC
    Inventors: Michael Xuefei Tang, Ming Sun, Dimitar V. Dimitrov, Patrick Ryan
  • Patent number: 7817375
    Abstract: A magnetic recording head includes a spin wave oscillator having a lamination film including a first magnetic layer and a second magnetic layer, and a pair of electrodes adapted to inject a current between the first magnetic layer and the second magnetic layer to generate a spin wave in one of the first magnetic layer and the second magnetic layer; and a recording magnetic pole provided on one side with the spin wave oscillator, the spin wave oscillator locally heating the recording track prior to recording by the recording magnetic pole.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: October 19, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Rie Sato, Koichi Mizushima
  • Patent number: 7813087
    Abstract: A magnetic memory device includes a magnetic tunnel junction element having a plurality of ferromagnetic layers stacked with a dielectric layer interposed between the adjacent ferromagnetic layers and storing magnetic information through reversal of magnetization of at least one of the magnetization layers, and a spin wave oscillator having a magnetization free layer, a nonmagnetic layer stacked on the magnetization free layer, a magnetization pinned layer stacked on the nonmagnetic layer, and a pair of electrodes adapted to apply current in the direction perpendicular to the surface of the magnetization free layer, the nonmagnetic layer and the magnetization pinned layer to thereby generate a spin wave. The spin wave oscillator is arranged in vicinity of the magnetic tunnel junction element to allow heating of the magnetic tunnel junction element and reversal of magnetization.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: October 12, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Rie Sato, Koichi Mizushima
  • Patent number: 7810227
    Abstract: Using a beam of xenon ions together with a suitable mask, a GMR stack is ion milled until a part of it, no more than about 0.1 microns thick, has been removed so that a pedestal, having sidewalls comprising a vertical section that includes all of the free layer, has been formed. This is followed by formation of the dielectric and conductive lead layers in the usual way. Using xenon as the sputtering gas enables the point at which milling is terminated to be more precisely controlled.
    Type: Grant
    Filed: October 18, 2007
    Date of Patent: October 12, 2010
    Assignees: Headway Technologies, Inc., TDK Corporation
    Inventors: Stuart Kao, Chunping Luo, Chaopeng Chen, Takahiko Machita, Daisuke Miyauchi, Jeiwei Chang
  • Patent number: 7810228
    Abstract: An example method for manufacturing a magneto-resistance effect element involves irradiating inert gas ions to enhance an adhesive force between an area around an oxide layer and a metallic layer.
    Type: Grant
    Filed: July 5, 2007
    Date of Patent: October 12, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji
  • Patent number: 7813086
    Abstract: Producing a thin film magnetic head includes forming a pair of openings in a predetermined region of a TMR layer formed on a lower magnetic shield layer; forming a pair of bias-applying layers in the pair of openings so that an upper surface thereof is located above an upper surface of the TMR layer; laminating a metal layer that covers the upper surface of a portion located between the pair of bias-applying layers in the TMR layer and the upper surface of the pair of bias-applying layers; forming a resist layer across the upper surface of a portion located above the pair of bias-applying layers in the metal layer and the upper surface of a portion located above the TMR layer in the metal layer; and etching a part of the TMR layer and a part of the pair of bias-applying layers with the resist layer being as a mask.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: October 12, 2010
    Assignee: TDK Corporation
    Inventors: Kosuke Tanaka, Kazuki Sato, Eiji Komura
  • Patent number: 7808750
    Abstract: The thin-film magnetic head of the invention comprises a magneto-resistive effect device including a multilayer film and a bias mechanism portion including a bias magnetic field-applying layer formed on each widthwise end of the multilayer film. When the magneto-resistive effective device including a multilayer film and the bias mechanism portion are viewed in plane on their own, the uppermost extremity of the rear end of the magneto-resistive effect device and the uppermost extremity of the rear end of the bias mechanism portion lie at substantially the same depth-wise position, and the rear slant of the bias mechanism portion is gentler in gradient than the rear slat of the magneto-resistive effect device. It is thus possible just only to facilitate the fabrication of the device but also to achieve several advantages of being a lower rate of occurrence of noise, higher reliability and higher yields.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: October 5, 2010
    Assignee: TDK Corporation
    Inventors: Takumi Yanagisawa, Takayasu Kanaya
  • Patent number: 7808748
    Abstract: A pinned layer of an MR element includes an underlying magnetic layer made of a magnetic alloy layer having a body-centered cubic structure, and a Heusler alloy layer formed on the underlying magnetic layer. A free layer of the MR element includes an underlying magnetic layer made of a magnetic alloy layer having a body-centered cubic structure, and a Heusler alloy layer formed on the underlying magnetic layer. Each of these two Heusler alloy layers is made of a CoMnSi alloy having an Mn content higher than 25 atomic percent and lower than or equal to 40 atomic percent, and contains a principal component having a B2 structure in which Co atoms are placed at body-centered positions of unit cells and Mn atoms or Si atoms are randomly placed at vertexes of the unit cells.
    Type: Grant
    Filed: February 22, 2007
    Date of Patent: October 5, 2010
    Assignee: TDK Corporation
    Inventors: Tomohito Mizuno, Yoshihiro Tsuchiya, Keita Kawamori
  • Patent number: 7808747
    Abstract: A magnetoresistive effect element includes a fixed magnetization layer; a free magnetization layer; a nonmagnetic spacer layer between the fixed magnetization layer and the free magnetization layer; and an insertion layer disposed on an opposite side of the free magnetization layer from the nonmagnetic spacer layer, wherein the first insulating layer has an oxide, a nitride, or an oxynitride including at least one kind of element selected from a group constituted of Al (aluminum), Si (silicon), Mg (magnesium), Ta (tantalum) and Zn (zinc) as a major constituent, and the insertion layer has an oxide, a nitride, or an oxynitride including at least one kind of element selected from a group constituted of Al (aluminum), Si (silicon), Mg (magnesium), Ta (tantalum) and Zn (zinc) as a major constituent.
    Type: Grant
    Filed: February 6, 2007
    Date of Patent: October 5, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7808749
    Abstract: A magnetoresistance effect element which is used in a magnetic sensor is disclosed. The magnetoresistance effect element includes a soft layer whose magnetization easy direction is changed by a direction of an external magnetic field, and a magnetization fixing layer whose magnetization direction is fixed by having a magnetic layer and an anti-ferromagnetic layer. A magnetoresistance effect is generated by a change of electric conduction which is caused by a relative angle between the magnetization easy direction of the soft layer and the magnetization direction of the magnetization fixing layer. When the magnetic sensor includes two or more magnetoresistance effect elements for having two-axis or more vectors of the magnetization directions, the two or more magnetoresistance effect elements are adjacently disposed.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: October 5, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Futoyoshi Kou
  • Patent number: 7800866
    Abstract: A magnetic sensing element is described, including a multilayer film including a pinned magnetic layer, a free magnetic layer disposed on the pinned magnetic layer with a nonmagnetic layer therebetween, wherein a current flows perpendicular to the surfaces of the individual layers of the multilayer film. The nonmagnetic layer is composed of Cu and has a face-centered cubic lattice crystal structure in which the {111} planes are preferentially oriented in a direction parallel to the surfaces of the layer. At least one of the pinned magnetic layer and the free magnetic layer includes a Co2Mn(Ge1-xSnx) alloy layer, the subscript x satisfying the range of 0.2?x?0.8; and the Co2Mn(Ge1-xSnx) alloy layer has a body-centered cubic lattice crystal structure in which the {110} planes are preferentially oriented in a direction parallel to the surfaces of the layer.
    Type: Grant
    Filed: March 22, 2006
    Date of Patent: September 21, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7795696
    Abstract: A magnetoresistive memory element has a read module with a first pinned layer that has a magnetoresistance that is readable by a read current received from an external circuit. The element has a write module that receives a write current from the external circuit. A coupling module adjacent both the write module and the read module has a free layer that functions as a shared storage layer for both the read module and the write module. The shared storage layer receives spin torque from both the read module and the write module and has a magnetization that is rotatable by the write current.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: September 14, 2010
    Assignee: Seagate Technology LLC
    Inventors: Oleg N. Mryasov, Thomas F. Ambrose, Werner Scholz
  • Patent number: 7784171
    Abstract: A method is provided for manufacturing a magneto-resistive device. The magneto-resistive device is for reducing the deterioration in the characteristics of the device due to annealing. The magneto-resistive device has a magneto-resistive layer formed on one surface side of a base, and an insulating layer formed of two layers and deposited around the magneto-resistive layer. The layer of the insulating layer closest to the base is made of a metal or semiconductor oxide. This layer extends over end faces of a plurality of layers made of different materials from one another, which make up the magneto-resistive device, and is in contact with the end faces of the plurality of layers with the same materials.
    Type: Grant
    Filed: May 4, 2007
    Date of Patent: August 31, 2010
    Assignee: TDK Corporation
    Inventors: Takeo Kagami, Tetsuya Kuwashima, Norio Takahashi
  • Patent number: 7782575
    Abstract: An MR element includes: a free layer having a direction of magnetization that changes in response to a signal magnetic field; a pinned layer having a fixed direction of magnetization; and a spacer layer disposed between these layers. The spacer layer includes a first nonmagnetic metal layer and a second nonmagnetic metal layer each made of a nonmagnetic metal material, and a semiconductor layer that is made of a material containing an oxide semiconductor and that is disposed between the first and second nonmagnetic metal layers. The MR element has a resistance-area product within a range of 0.1 to 0.3?·?m2, and the spacer layer has a conductivity within a range of 133 to 432 S/cm.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: August 24, 2010
    Assignee: TDK Corporation
    Inventors: Yoshihiro Tsuchiya, Kei Hirata, Tomohito Mizuno, Koji Shimazawa
  • Patent number: 7782577
    Abstract: A magnetic random access memory structure comprising an anti-ferromagnetic layer structure, a crystalline ferromagnetic structure physically coupled to the anti-ferromagnetic layer structure and a ferromagnetic free layer structure physically coupled to the crystalline ferromagnetic structure.
    Type: Grant
    Filed: June 6, 2006
    Date of Patent: August 24, 2010
    Assignees: Infineon Technologies AG, ALTIS Semiconductor, SNC
    Inventors: Wolfgang Raberg, Ulrich Klostermann
  • Patent number: 7764470
    Abstract: A magneto-resistance effect element used for a thin film magnetic head is configured by a buffer layer, an anti-ferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer, which are laminated in this order, and a sense current flows through the element in a direction orthogonal to the layer surface, via a lower shield layer and a upper shield layer. The pinned layer comprises an outer layer in which a magnetization direction is fixed, a non-magnetic intermediate layer, and an inner layer which is a ferromagnetic layer. The spacer layer comprises a first and second non-magnetic metal layer, and a semiconductor layer. The first and second non-magnetic metal layer and comprise CuPt films having a thickness of more than 0 nm but no more than 2.0 nm, and the Pt content ranges from a minimum of 5 to a maximum of 25 at %.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: July 27, 2010
    Assignee: TDK Corporation
    Inventors: Tomohito Mizuno, Kei Hirata, Yoshihiro Tsuchiya, Koji Shimazawa
  • Patent number: 7764471
    Abstract: A magnetoresistance effect element (MR element) for use in a thin-film magnetic head has a buffer layer, an antiferromagnetic layer, a pinned layer, a spacer layer, a free layer, and a cap layer that are successively stacked. A sense current flows in a direction perpendicular to layer surfaces via a lower shield layer and an upper shield layer. The pinned layer comprises an outer layer having a fixed magnetization direction, a nonmagnetic intermediate layer, and an inner layer in the form of a ferromagnetic layer. The spacer layer comprises a first nonmagnetic metal layer, a semiconductor layer made of ZnO, and a second nonmagnetic metal layer. The inner layer or the outer layer includes a diffusion blocking layer made of an oxide of an element whose electronegativity is equal to or smaller than Zn, e.g., ZnO, TaO, ZrO, MgO, TiO, or HfO, or made of RuO.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: July 27, 2010
    Assignee: TDK Corporation
    Inventors: Tomohito Mizuno, Takahiko Machita, Kei Hirata, Yoshihiro Tsuchiya, Shinji Hara
  • Publication number: 20100177447
    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: Application
    Filed: January 9, 2009
    Publication date: July 15, 2010
    Applicant: TDK CORPORATION
    Inventor: Takumi YANAGISAWA
  • Patent number: 7746601
    Abstract: An area of an element can be made small and fluctuation in area can be reduced. A magneto-resistance effect element is provided with a first electrode with an end face; a magneto-resistance effect film which is formed such that a surface thereof comes in contact with the end face of the first electrode; and a second electrode which is formed on another surface of the magneto-resistance effect element opposed from the surface coming in contact with the surface of the first electrode. The magneto-resistance effect film includes a magnetization pinned layer whose magnetization direction is pinned, a magnetization free layer whose magnetization direction is changeable, and a first non-magnetic layer which is provided between the magnetization pinned layer and the magnetization free layer.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: June 29, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideyuki Sugiyama, Yoshiaki Saito