Detail Of Pinned Film Or Additional Film For Affecting Or Biasing The Pinned Film Patents (Class 360/324.11)
  • Patent number: 8300356
    Abstract: A spin transfer oscillator with a seed/SIL/spacer/FGL/capping configuration is disclosed with a composite seed layer made of Ta and a metal layer having a fcc(111) or hcp(001) texture to enhance perpendicular magnetic anisotropy (PMA) in an overlying (A1/A2)X laminated spin injection layer (SIL). Field generation layer (FGL) is made of a high Bs material such FeCo. Alternatively, the STO has a seed/FGL/spacer/SIL/capping configuration. The SIL may include a FeCo layer that is exchanged coupled with the (A1/A2)X laminate (x is 5 to 50) to improve robustness. The FGL may include an (A1/A2)Y laminate (y=5 to 30) exchange coupled with the high Bs layer to enable easier oscillations. A1 may be one of Co, CoFe, or CoFeR where R is a metal, and A2 is one of Ni, NiCo, or NiFe. The STO may be formed between a main pole and trailing shield in a write head.
    Type: Grant
    Filed: May 11, 2010
    Date of Patent: October 30, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Yuchen Zhou
  • Patent number: 8300367
    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 3, 2011
    Date of Patent: October 30, 2012
    Assignee: HGST Netherlands, B.V.
    Inventors: James M. Freitag, Mustafa M. Pinarbasi
  • Patent number: 8288023
    Abstract: A magnetic tunnel junction cell having a free layer, a ferromagnetic pinned layer, and a barrier layer therebetween. The free layer has a central ferromagnetic portion and a stabilizing portion radially proximate the central ferromagnetic portion. The construction can be used for both in-plane magnetic memory cells where the magnetization orientation of the magnetic layer is in the stack film plane and out-of-plane magnetic memory cells where the magnetization orientation of the magnetic layer is out of the stack film plane, e.g., perpendicular to the stack plane.
    Type: Grant
    Filed: December 23, 2010
    Date of Patent: October 16, 2012
    Assignee: Seagate Technology LLC
    Inventors: Kaizhong Gao, Haiwen Xi
  • Patent number: 8274764
    Abstract: A magneto-resistive effect (MR) element includes a first magnetic layer and a second magnetic layer in which a relative angle of magnetization directions of the first and second magnetic layers changes according to an external magnetic field; and a spacer layer that is provided between the first magnetic layer and the second magnetic layer. The spacer layer contains gallium nitride (GaN) as a main component.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: September 25, 2012
    Assignee: TDK Corporation
    Inventors: Shinji Hara, Yoshihiro Tsuchiya, Tsutomu Chou, Hironobu Matsuzawa
  • Patent number: 8274766
    Abstract: A magneto-resistive element includes: a first magnetic layer having a substantially fixed magnetization direction; a thin film layer disposed on the first magnetic layer and having at least one of oxide, nitride, oxynitride, and metal; and a second magnetic layer disposed on the thin film layer and having a substantially fixed magnetization direction.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: September 25, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yoshihiko Fuji, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 8270125
    Abstract: A magnetoresistive tunnel junction sensor having improved free layer stability, as well as improved free sensitivity. The free layer is constructed to have a low magnetic coercivity which improves free layer sensitivity. The free layer is also constructed to have a negative magnetostriction which improves free layer stability by preventing the free layer from having an easy axis that is oriented perpendicular to the air bearing surface.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: September 18, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal Singh Gill
  • Publication number: 20120229936
    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: May 25, 2012
    Publication date: September 13, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa, Michiko Hara, Shuichi Murakami
  • Patent number: 8264800
    Abstract: A magnetic field detecting element has a first lower layer, a second lower layer, a tunnel barrier layer, and an upper layer, wherein the first lower layer, the second lower layer, the tunnel barrier layer, and the upper layer are stacked adjacent to each other in this order, the first lower layer is formed in an amorphous state; and the second lower layer is made of cobalt, iron, nickel or a combination thereof and that is formed in a substantially amorphous state, the second lower layer being in touch with the first lower layer and the tunnel barrier layer on both sides and a film thickness of the second lower layer is approximately between 0.2 and 1.5 nm.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: September 11, 2012
    Assignee: TDK Corporation
    Inventors: Takumi Uesugi, Satoshi Miura
  • Publication number: 20120224283
    Abstract: According to one embodiment, a three-dimensional magnetic recording and reproducing apparatus includes a magnetic head and a magnetic storage medium. The magnetic head includes a spin-torque oscillator including a free layer, a non-magnetic layer and a fixed layer, magnetization of the free layer being rotatable, the non-magnetic layer being laminated on the free layer, the fixed layer being laminated on the non-magnetic layer, a magnetization direction of the fixed layer being fixed. The magnetic storage medium includes first magnetic layers formed of magnetic materials having different resonant frequencies, each of the first magnetic layers being formed of an in-plane magnetization film and having recording tracks.
    Type: Application
    Filed: March 9, 2012
    Publication date: September 6, 2012
    Inventors: Rie SATO, Koichi Mizushima, Tazumi Nagasawa, Kiwamu Kudo
  • Publication number: 20120218667
    Abstract: According to one embodiment, a magnetic oscillator includes a layered film and a pair of electrodes. The layered film includes a first ferromagnetic layer, an insulating layer stacked on the first ferromagnetic layer, and a second ferromagnetic layer stacked on the insulating layer. The pair of electrodes is configured to apply a current to the layered film in a direction perpendicular to a film surface of the layered film. Regions having different resistance area products are provided between the first ferromagnetic layer and the second ferromagnetic layer.
    Type: Application
    Filed: March 26, 2012
    Publication date: August 30, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tazumi NAGASAWA, Kiwamu KUDO, Rie SATO, Koichi MIZUSHIMA
  • Publication number: 20120206839
    Abstract: A magnetoresistive device includes a free layer, a separating layer, a pinned layer, and a magnetic stabilizer in close proximity to the pinned layer, wherein the magnetic stabilizer may enhance the stability of the magnetization direction of the pinned layer.
    Type: Application
    Filed: April 26, 2012
    Publication date: August 16, 2012
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Song Sheng Xue, Paul Edward Anderson, Konstantin Rudolfovich Nikolaev, Patrick Joseph Ryan
  • Patent number: 8240026
    Abstract: A method 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: September 24, 2008
    Date of Patent: August 14, 2012
    Assignee: TDK Corporation
    Inventors: Takeo Kagami, Tetsuya Kuwashima, Norio Takahashi
  • Patent number: 8238063
    Abstract: A magnetic sensor assembly including first and second shields, and a sensor stack between the first and second shields. The sensor stack includes a seed layer adjacent the first shield, a cap layer adjacent the second shield, and a magnetic sensor between the seed layer and the cap layer, wherein at least one of the seed layer and the cap layer has a synthetic antiferromagnetic structure.
    Type: Grant
    Filed: July 7, 2009
    Date of Patent: August 7, 2012
    Assignee: Seagate Technology LLC
    Inventors: Jiaoming Qiu, Hao Meng, Yonghua Chen
  • Patent number: 8225487
    Abstract: A method according to one embodiment includes forming a mask above a thin film sensor stack; forming an electrically insulating layer above the mask and sensor stack, the insulating layer having a portion extending along a nonhorizontal end of the mask; selectively removing the insulating layer except for the portion thereof extending along the nonhorizontal end of the mask; removing portions of the sensor stack that are not covered by the mask and the portion of the insulating layer, wherein an end of the portion of the insulating layer positioned away from the mask is about aligned with a back end of the sensor stack after removing the portions thereof; and removing the mask.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: July 24, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Ying Hong, Edward Hin Pong Lee, Aron Pentek, David John Seagle
  • Patent number: 8225489
    Abstract: An MR element includes a first exchange coupling shield layer, an MR stack, and a second exchange coupling shield layer that are arranged in this order from the bottom, and a nonmagnetic layer surrounding the MR stack. The MR stack includes a first free layer, a spacer layer, a second free layer, and a magnetic cap layer that are arranged in this order from the bottom. In the step of forming the MR stack and the nonmagnetic layer, a protection layer is formed on a layered film that will be the MR stack later, and a mask is then formed on the protection layer. Next, the layered film and the protection layer are etched using the mask and then the nonmagnetic layer is formed. After removal of the mask, the protection layer is removed by wet etching.
    Type: Grant
    Filed: March 26, 2010
    Date of Patent: July 24, 2012
    Assignee: TDK Corporation
    Inventors: Daisuke Miyauchi, Takahiko Machita, Keita Kawamori
  • Patent number: 8216703
    Abstract: A magnetic tunnel junction (MTJ) (10) employing a dielectric tunneling barrier (16), useful in magnetoresistive random access memories (MRAMs) and other devices, has a synthetic antiferromagnet (SAF) structure (14, 16), comprising two ferromagnetic (FM) layers (26, 41; 51, 58; 61, 68) separated by a coupling layer (38, 56, 66). Improved magnetoresistance (MR) ratio is obtained by providing a further layer (44, 46, 46?, 47, 52, 62), e.g. containing Ta, preferably spaced apart from the coupling layer (38, 56, 66) by a FM layer (41, 30-2, 54). The further layer (44, 46, 46?, 47, 52, 62) may be a Ta dusting layer (44) covered by a FM layer (30-2), or a Ta containing FM alloyed layer (46), or a stack (46?) of interleaved FM and N-FM layers, or other combination (47, 62). Furthering these benefits, another FM layer, e.g., CoFe, NiFe, (30, 30-1, 51, 61) is desirably provided between the further layer (44, 46, 46?, 47, 52, 62) and the tunneling barrier (16).
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: July 10, 2012
    Assignee: Everspin Technologies, Inc.
    Inventors: Jijun Sun, Jon M. Slaughter
  • Patent number: 8208230
    Abstract: We disclose a magnetic read head, and method for making it, that operates in a binary rather than an analog mode. This greatly boosts signal amplitude for high area density recording as device dimensions get smaller. The device is well suited to the inclusion of side shields which further reduces side reading errors. The device has a utilization efficiency close to 100%.
    Type: Grant
    Filed: April 10, 2008
    Date of Patent: June 26, 2012
    Assignee: Headway Technologies, Inc.
    Inventor: Yue Liu
  • Patent number: 8203389
    Abstract: A spin transfer oscillator (STO) device is disclosed with a giant magnetoresistive (GMR) junction comprising a magnetic resistance layer (MRL)/spacer/magnetic oscillation layer (MOL) configuration, and a MR sensor including a sensing layer/junction layer/reference layer configuration. MOL and sensing layer are magnetostatically coupled and separated by a conductive spacer. MRL has perpendicular magnetic anisotropy while MOL and sensing layer have a Mst (saturation magnetization×thickness) value within ±50% of each other. When a magnetic field is applied perpendicular to the planes of the MOL and a high density current flows from the conductive spacer to the MRL, a MOL oscillation state with a certain frequency is induced. Consequently, the sensing layer oscillates with a similar RF frequency and when a low density current flows across the MR sensor, an AC voltage signal is generated to determine the sensing layer frequency that can be varied by adjusting the applied field.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: June 19, 2012
    Assignee: Headway Technologies, Inc.
    Inventors: Yuchen Zhou, Kunliang Zhang, Pokang Wang, Joe Smyth
  • Patent number: 8197953
    Abstract: A magnetic stack having a free layer having a switchable magnetization orientation, a reference layer having a pinned magnetization orientation, and a barrier layer therebetween. The stack includes an annular antiferromagnetic pinning layer electrically isolated from the free layer and in physical contact with the reference layer. In some embodiments, the reference layer is larger than the free layer.
    Type: Grant
    Filed: April 11, 2011
    Date of Patent: June 12, 2012
    Assignee: Seagate Technology LLC
    Inventors: Haiwen Xi, Antoine Khoueir, Brian Lee, Pat Ryan, Michael Tang, Insik Jin, Paul E. Anderson
  • Patent number: 8191235
    Abstract: The method of the present invention provides a magnetoresistance effect element, which is capable of having a high MR ratio, corresponding to high density recording and being suitably applied to a magnetoresistance device even though a barrier layer is thinned to reduce resistance of the magnetoresistance effect element. The method of producing the magnetoresistance effect element, which includes the barrier layer composed of an oxidized metal, a first magnetic layer contacting one of surfaces of the barrier layer and a second magnetic layer contacting the other surface thereof, comprises the steps of: laminating the barrier layer on the first magnetic layer with using a target composed of the oxidized metal; and laminating the second magnetic layer on the barrier layer. The barrier layer is annealed before laminating the second magnetic layer thereon.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: June 5, 2012
    Assignees: Fujitsu Limited, Tohoku University
    Inventors: Migaku Takahashi, Masakiyo Tsunoda, Koujiro Komagaki, Yuji Uehara, Kazuyuki Sunaga
  • Patent number: 8194361
    Abstract: It is made possible to provide a spin-torque oscillator that has a high Q value and a high output. A spin-torque oscillator includes: an oscillating field generating unit configured to generate an oscillating field; and a magnetoresistive element including a magnetoresistive effect film including a first magnetization pinned layer of which a magnetization direction is pinned, a first magnetization free layer of which a magnetization direction oscillates with the oscillating field, and a first spacer layer interposed between the first magnetization pinned layer and the first magnetization free layer.
    Type: Grant
    Filed: September 29, 2008
    Date of Patent: June 5, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kiwamu Kudo, Tazumi Nagasawa, Koichi Mizushima, Rie Sato
  • Patent number: 8194362
    Abstract: A magnetoresistive effect device includes an underlayer, an antiferromagnetic layer, a first ferromagnetic layer, a nonmagnetic layer, and a second ferromagnetic layer which are multilayered in this order on a substrate. The underlayer is formed of a metal nitride, and the antiferromagnetic layer is formed of an antiferromagnetic material including Ir and Mn.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: June 5, 2012
    Assignee: Fujitsu Limited
    Inventors: Takahiro Ibusuki, Masashige Sato, Shinjiro Umehara
  • Patent number: 8188558
    Abstract: In order to increase an efficiency of spin transfer and thereby reduce the required switching current, a current perpendicular to plane (CPP) magnetic element for a memory device includes either one or both of a free magnetic layer, which has an electronically reflective surface, and a permanent magnet layer, which has perpendicular anisotropy to bias the free magnetic layer.
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: May 29, 2012
    Assignee: Seagate Technology LLC
    Inventors: Dexin Wang, Dimitar V. Dimitrov, Song S. Xue, Insik Jin
  • Patent number: 8189304
    Abstract: A magnetoresistive magnetic head according to one embodiment uses a current-perpendicular-to-plane magnetoresistive element having a laminate of a free layer, an intermediate layer, and a pinned layer, the pinned layer being substantially fixed to a magnetic field to be detected, wherein either the pinned layer or the free layer includes a Heusler alloy layer represented by a composition of X—Y—Z, wherein X is between about 45 at. % and about 55 at. % and is Co or Fe, Y accounts for between about 20 at. % and about 30 at. % and is one or more elements selected from V, Cr, Mn, and Fe, and Z is between about 20 at. % and about 35 at.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: May 29, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Susumu Okamura, Yo Sato, Katsumi Hoshino, Hiroyuki Hoshiya, Kenichi Meguro, Keizo Kato
  • Patent number: 8184408
    Abstract: A magnetoresistive element includes a magnetoresistive film including a magnetization pinned layer, a magnetization free layer, an intermediate layer arranged between the magnetization pinned layer and the magnetization free layer, a cap layer arranged on the magnetization pinned layer or on the magnetization free layer, and a functional layer formed of an oxygen- or nitrogen-containing material and arranged in the magnetization pinned layer, or in the magnetization free layer, and a pair of electrodes which pass a current perpendicularly to a plane of the magnetoresistive film, in which a crystalline orientation plane of the functional layer is different from a crystalline orientation plane of its upper or lower adjacent layer.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: May 22, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shuichi Murakami, Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji
  • Patent number: 8184407
    Abstract: An underlying layer (2) made of NiFeN is disposed over the principal surface of a substrate. A pinning layer (3) made of antiferromagnetic material containing Ir and Mn is disposed on the underlying layer. A reference layer (4c) made of ferromagnetic material whose magnetization direction is fixed through exchange-coupling with the pinning layer directly or via another ferromagnetic material layer, is disposed over the pinning layer. A nonmagnetic layer (7) made of nonmagnetic material is disposed over the reference layer. A free layer (8) made of ferromagnetic material whose magnetization direction changes in dependence upon an external magnetic field, is disposed over the nonmagnetic layer.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: May 22, 2012
    Assignee: Fujitsu Limited
    Inventors: Takahiro Ibusuki, Masashige Sato, Shinjiro Umehara
  • Patent number: 8184409
    Abstract: A magnetoresistive device includes a free layer, a separating layer, a pinned layer, and a magnetic stabilizer in close proximity to the pinned layer, wherein the magnetic stabilizer may enhance the stability of the magnetization direction of the pinned layer.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: May 22, 2012
    Assignee: Seagate Technology LLC
    Inventors: Song Sheng Xue, Paul Edward Anderson, Konstantin Rudolfovich Nikolaev, Patrick Joseph Ryan
  • Publication number: 20120120520
    Abstract: A CPP spin-valve magnetic head, according to one embodiment includes a ferromagnetic free layer having a bias-point magnetization nominally oriented in a first direction; a ferromagnetic reference layer film having a bias-point magnetization nominally oriented in a second direction that is not orthogonal to the said first direction; and a tunnel barrier layer between the free and reference layers.
    Type: Application
    Filed: January 26, 2012
    Publication date: May 17, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Jeffrey Robinson Childress, Neil Smith
  • Patent number: 8176622
    Abstract: A process for manufacturing a high performance MTJ it is described: A first cap layer of NiFeHf is deposited on the free layer, followed by a second cap layer of Ru on Ta. The device is then heated so that oxygen trapped in the free layer diffuses into the NiFeHf layer, thereby sharpening the interface between the tunnel barrier layer and the free layer.
    Type: Grant
    Filed: January 27, 2010
    Date of Patent: May 15, 2012
    Assignee: MagIC Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong, Chyu-Jiuh Torng, Witold Kula
  • Patent number: 8174800
    Abstract: A magnetoresistive element includes an antiferromagnetic layer formed from a layer containing manganese, a layered magnetization fixed layer which includes a first magnetization fixed layer located over a side of the antiferromagnetic layer and formed from a layer containing a ferromagnetic material and a platinum group metal, a second magnetization fixed layer formed from a layer containing a ferromagnetic material, and a first nonmagnetic intermediate layer located between the first magnetization fixed layer and the second magnetization fixed layer, a magnetic free layer formed from a layer containing a ferromagnetic material, and a second nonmagnetic intermediate layer located between the layered magnetization fixed layer and the magnetic free layer.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: May 8, 2012
    Assignee: Canon Anelva Corporation
    Inventors: Koji Tsunekawa, David Djayaprawira
  • Patent number: 8166633
    Abstract: A method for manufacturing an extraordinary magnetoresistive sensor (EMR sensor) having reduced size and increased resolution is described. The sensor includes a plurality of electrically conductive leads contacting a magnetically active layer and also includes an electrically conductive shunt structure. The electrically conductive leads of the sensor and the shunt structure can be formed in a common photolithographic masking and etching process so that they are self aligned with one another. This avoids the need to align multiple photolithographic processing steps, thereby allowing greatly increased resolution and reduced lead spacing. The EMR sensor can be formed with a magnetically active layer that can be close to or at the air bearing surface (ABS) for improved magnetic spacing with an adjacent magnetic medium of a data recording system.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: May 1, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Thomas Dudley Boone, Jr., Liesl Folks, Bruce Alvin Gurney, Jordan Asher Katine, Ernesto E. Marinero, Neil Smith
  • Patent number: 8154825
    Abstract: It is made possible to provide a magnetic head that can stabilize the high-frequency magnetic field generated from the spin torque oscillator. A magnetic head includes: first and second main magnetic poles; and a spin torque oscillator provided between the first and second main magnetic poles.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masahiro Takashita, Hitoshi Iwasaki, Kenichiro Yamada, Junichi Akiyama, Masayuki Takagishi, Tomomi Funayama, Mariko Shimizu
  • Patent number: 8151442
    Abstract: Magnetoresistive (MR) elements having flux guides defined by the free layer. The MR element includes a free layer, a spacer/barrier layer, a pinned layer, and a pinning layer. A back edge of the free layer (opposite the sensing surface of the MR element) extends past a back edge of the spacer/barrier layer. The portion of the free layer extending past the back edge of the spacer/barrier layer defines a continuous flux guide. The flux guide is processed to reduce the conductive characteristics of the flux guide, thereby reducing current shunt loss in the flux guide.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: April 10, 2012
    Assignee: Hitachi Global Strorage Technologies Netherlands, B.V.
    Inventor: Hardayal S. Gill
  • Patent number: 8136227
    Abstract: A magnetic head having non-GMR shunt for perpendicular recording and method for making magnetic head having non-GMR shunt for perpendicular recording is disclosed. A shunt is provided for shunting charge from a read sensor. The shunt is formed co-planar with the read sensor and is fabricated using non-GMR materials.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: March 20, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Michael Feldbaum, Quang Le, Edward H. Lee, Neil L. Robertson, Charles G. Seegel, III
  • Patent number: 8139324
    Abstract: To provide a magnetic head that is suited for high recording density magnetic read and write, and has little noise. A magnetic pinned layer is formed on a non-magnetic electrode layer via a first insulating layer, and a magnetic free layer is formed on a medium-side plane of the non-magnetic electrode layer via a second insulating layer. A circuit for flowing current between the non-magnetic electrode layer and the magnetic pinned layer via the first insulating layer, and a circuit for measuring voltage between the non-magnetic electrode layer and the magnetic free layer are connected to the magnetic free layer. The medium-side plane on which the magnetic free layer is formed may be a plane substantially parallel to the surface of the medium, or may be a plane tilted from the surface of the medium.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: March 20, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Hiromasa Takahashi, Masaki Yamada
  • Patent number: 8116043
    Abstract: A method and system for providing a magnetic structure in magnetic transducer is described. The method and system include providing a pinning layer, a synthetic antiferromagnetic (SAF) adjacent to the pinning layer, a nonmagnetic layer, and a sensor layer. The SAF resides between the nonmagnetic and pinning layers. The nonmagnetic layer is between the SAF and the sensor layer. The SAF includes a pinned layer, a reference layer, and a nonmagnetic spacer layer between the pinned and reference layers. The pinned layer is magnetically coupled with the reference layer and includes sublayers. A first sublayer has a first blocking temperature distribution (TBD) and a first exchange energy. A second sublayer has a second TBD and a second exchange energy. The first sublayer is between the pinning layer and second sublayer. The first TBD is greater than the second TBD. The first exchange energy is less than the second exchange energy.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: February 14, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Qunwen Leng, Jian X. Shen, Feng Liu, Geoffrey W. Anderson
  • Patent number: 8094421
    Abstract: A current-to-perpendicular-to-plane (CPP) read sensor with multiple reference layers and associated fabrication methods are disclosed. According to one embodiment of the invention, the multiple reference layers of a CPP tunneling magnetoresistance (TMR) read sensor includes a first reference layer formed by a ferromagnetic polycrystalline Co—Fe film, a second reference layer formed by a ferromagnetic substitute-type amorphous Co—Fe—X film where X is Hf, Zr or Y, and a third reference layer formed by a ferromagnetic interstitial-type amorphous Co—Fe—B film. The first reference layer facilitates the CPP TMR read sensor to exhibit high exchange and antiparallel-coupling fields. The second reference layer provides a thermally stable flat surface, thus facilitating the CPP TMR read sensor to exhibit a low ferromagnetic-coupling field. The multiple reference layers may induce spin-dependent scattering, thus facilitating the CPP TMR sensor to exhibit a high TMR coefficient.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: January 10, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventor: Tsann Lin
  • Patent number: 8085511
    Abstract: A magnetoresistance effect element includes a magnetoresistance effect film including a magnetically pinned layer having a magnetic material film whose direction of magnetization is pinned substantially in one direction, a magnetically free layer having a magnetic material film whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic metal intermediate layer located between said pinned layer and said free layer. The element also includes a pair of electrodes electrically connected to the magnetoresistance effect film to supply a sense current perpendicularly to a film plane of the magnetoresistance effect film. At least one of the pinned layer and the free layer may include a thin-film insertion layer.
    Type: Grant
    Filed: September 23, 2008
    Date of Patent: December 27, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Yuzo Kamiguchi, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Tomohiko Nagata, Takeo Sakakubo, Masashi Sahashi
  • Patent number: 8072800
    Abstract: Techniques and magnetic devices associated with a magnetic element that includes a fixed layer having a fixed layer magnetization and perpendicular anisotropy, a nonmagnetic spacer layer, and a free layer having a changeable free layer magnetization and perpendicular anisotropy.
    Type: Grant
    Filed: September 15, 2009
    Date of Patent: December 6, 2011
    Assignee: Grandis Inc.
    Inventors: Eugene Youjun Chen, Shengyuan Wang
  • Patent number: 8068316
    Abstract: A magnetoresistive sensor including: a first pinned-magnetization magnetic layer and a free-magnetization magnetic layer, separated by first separating layer for magnetic uncoupling. The sensor further includes a second pinned-magnetization magnetic layer, separated from the free-magnetization magnetic layer by a second separating layer for magnetic uncoupling, the first and second separating layers being located on either side of the free-magnetization magnetic layer, and the respective magnetizations of the first pinned-magnetization magnetic layer and of the free-magnetization magnetic layer, in the absence of an external field, are substantially orthogonal. The orientation of the magnetization of the second pinned layer is selectable.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: November 29, 2011
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Bernard Dieny, Claire Baraduc, Sébastien Petit, Christophe Thirion
  • Patent number: 8068315
    Abstract: A magnetoresisive sensor having a thin seed layer that provides an exceptionally smooth interface between layers of the sensor stack. The exceptionally smooth interface provided by the seed layer reduces interlayer exchange coupling allowing the non-magnetic spacer layer (or barrier layer) to be very thin. The seed layer includes a thin layer of Ru and a thin layer of Si which intermix to form a homogeneous, amorphous thin seed layer of Ru-silicide.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: November 29, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: James Mac Freitag, Hardayal Singh Gill, Mustafa Michael Pinarbasi
  • Patent number: 8059374
    Abstract: A composite free layer having a FL1/insertion/FL2 configuration is disclosed for achieving high dR/R, low RA, and low ? in TMR or GMR sensors. Ferromagnetic FL1 and FL2 layers have (+) ? and (?) ? values, respectively. FL1 may be CoFe, CoFeB, or alloys thereof with Ni, Ta, Mn, Ti, W, Zr, Hf, Tb, or Nb. FL2 may be CoFe, NiFe, or alloys thereof with Ni, Ta, Mn, Ti, W, Zr, Hf, Tb, Nb, or B. The thin insertion layer includes at least one magnetic element such as Co, Fe, and Ni, and at least one non-magnetic element selected from Ta, Ti, W, Zr, Hf, Nb, Mo, V, Cr, or B. In a TMR stack with a MgO tunnel barrier, dR/R>60%, ?˜1×10?6, and RA=1.2 ohm-um2 when FL1 is CoFe/CoFeB/CoFe, FL2 is CoFe/NiFe/CoFe, and the insertion layer is CoTa or CoFeBTa.
    Type: Grant
    Filed: January 14, 2009
    Date of Patent: November 15, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Tong Zhao, Hui-Chuan Wang, Min Li, Kunliang Zhang
  • Patent number: 8054587
    Abstract: An MR element includes a lower shield layer, a magnetization free function part stacked on the lower shield layer, an upper shield layer stacked on the magnetization free function part, a nonmagnetic intermediate layer stacked on a surface, that is opposite to a magnetically sensitive surface, of the magnetization free function part, and a magnetization fixed function part stacked on the nonmagnetic intermediate layer. The nonmagnetic intermediate layer and the magnetization fixed function part are formed only within an outer region of the magnetization free function part, located opposite side to the magnetically sensitive surface.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: November 8, 2011
    Assignee: TDK Corporation
    Inventor: Takumi Yanagisawa
  • Patent number: 8048686
    Abstract: The invention relates to a method for producing a device comprising magnetic blocks magnetized in different directions, comprising steps of: a) forming, in a stack of one or more layers of at least one antiferromagnetic material and one or more layers of at least one ferromagnetic material resting on a substrate, at least one first block and at least one second block, said blocks being longilineal and separate and extending respectively in a first main direction and in a second main direction, the first and the second main direction forming between them a first non-zero angle ?, b) annealing said blocks at a temperature greater than the ordering temperature of said antiferromagnetic material or than the blocking temperature or than the Néel temperature of said antiferromagnetic material.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: November 1, 2011
    Assignee: Commissariat a l'Energie Atomic
    Inventor: Olivier Redon
  • Patent number: 8043732
    Abstract: Magnetic tunnel junction cells and methods of making magnetic tunnel junction cells that include a radially protective layer extending proximate at least the ferromagnetic free layer of the cell. The radially protective layer can be specifically chosen in thickness, deposition method, material composition, and/or extent along the cell layers to enhance the effective magnetic properties of the free layer, including the effective coercivity, effective magnetic anisotropy, effective dispersion in magnetic moment, or effective spin polarization.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: October 25, 2011
    Assignee: Seagate Technology LLC
    Inventors: Paul E. Anderson, Song S. Xue
  • Patent number: 8037593
    Abstract: A method for manufacturing a magnetoresistive sensor that decreases the stack height of the sensor. The method includes forming a sensor structure having at its top, a Ru layer and a Ta layer over the Ru layer. An annealing process is performed to set the magnetization of the pinned layer of the sensor structure. After the annealing process has been completed and the Ta layer is no longer needed, an ion milling process is performed to remove the Ta layer.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: October 18, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Kuok San Ho, Ying Hong, Wipul Pemsiri Jayasekara, Daniele Mauri
  • Patent number: 8036024
    Abstract: In a ferromagnetic tunnel junction element, a recording layer is in a circular shape, which can suppress an increase in magnetization switching field due to miniaturization of the element. Further, the recording layer includes a first ferromagnetic layer, a first non-magnetic layer, a second ferromagnetic layer, a second non-magnetic layer, and a third ferromagnetic layer successively stacked. The first and second ferromagnetic layers, and the second and third ferromagnetic layers are coupled antiparallel to each other, so that it is possible to control the magnetization distribution of the recording layer in an approximately single direction.
    Type: Grant
    Filed: May 30, 2006
    Date of Patent: October 11, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Takashi Takenaga, Takeharu Kuroiwa, Hiroshi Kobayashi, Sadeh Beysen
  • Patent number: 8031444
    Abstract: The semiconductor oxide layer that forms a part of the spacer layer in the inventive giant magnetoresistive device (CPP-GMR device) is composed of zinc oxide of wurtzite structure that is doped with a dopant given by at least one metal element selected from the group consisting of Zn, Ge, V, and Cr in a content of 0.05 to 0.90 at %: there is the advantage obtained that ever higher MR ratios are achievable while holding back an increase in the area resistivity AR.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: October 4, 2011
    Assignee: TDK Corporation
    Inventors: Tsutomu Chou, Tomohito Mizuno, Koji Shimazawa, Yoshihiro Tsuchiya, Shinji Hara, Hironobu Matsuzawa
  • Patent number: 8031441
    Abstract: A CPP-GMR spin valve having a composite spacer layer comprised of at least one metal (M) layer and at least one semiconductor or semi-metal (S) layer is disclosed. The composite spacer may have a M/S, S/M, M/S/M, S/M/S, M/S/M/S/M, or a multilayer (M/S/M)n configuration where n is an integer ?1. The pinned layer preferably has an AP2/coupling/AP1 configuration wherein the AP2 portion is a FCC trilayer represented by CoZFe(100-Z)/FeYCo(100-Y)/CoZFe(100-Z) where y is 0 to 60 atomic %, and z is 75 to 100 atomic %. In one embodiment, M is Cu with a thickness from 0.5 to 50 Angstroms and S is ZnO with a thickness of 1 to 50 Angstroms. The S layer may be doped with one or more elements. The dR/R ratio of the spin valve is increased to 10% or greater while maintaining acceptable EM and RA performance.
    Type: Grant
    Filed: May 11, 2007
    Date of Patent: October 4, 2011
    Assignee: Headway Technologies, Inc.
    Inventors: Kunliang Zhang, Min Li, Moris Dovek, Yue Liu
  • Patent number: 8018693
    Abstract: A magnetic detector includes a magnetoresistive element and an impact sensor. The magnetoresistive element has a plurality of element-constituent layers that are stacked and include a free layer having a magnetization direction that changes in response to a magnetic field to be detected by the magnetic detector. The impact sensor has a plurality of sensor-constituent layers that are made of materials the same as those of the element-constituent layers and stacked in the same order as the element-constituent layers. The plurality of sensor-constituent layers include an impact detecting layer corresponding to the free layer and having a magnetization direction that changes by an inverse magnetostrictive effect in response to distortion created in the impact detecting layer by an impact received by the magnetic detector. The impact detecting layer exhibits a greater amount of change in magnetization direction when the magnetic detector receives an impact, compared with the free layer.
    Type: Grant
    Filed: January 21, 2009
    Date of Patent: September 13, 2011
    Assignee: TDK Corporation
    Inventor: Takumi Yanagisawa