Having One Film Pinned (e.g., Spin Valve) Patents (Class 360/324.1)
  • Patent number: 7739787
    Abstract: In an MR element, each of a pinned layer and a free layer includes a Heusler alloy layer. The Heusler alloy layer has two surfaces that are quadrilateral in shape and face toward opposite directions. The Heusler alloy layer includes one crystal grain that touches four sides of one of the two surfaces. In a method of manufacturing the MR element, a layered film to be the MR element is formed and patterned, and then heat treatment is performed on the layered film patterned, so that crystal grains included in a film to be the Heusler alloy layer in the layered film grow and one crystal grain that touches four sides of one of the surfaces of the film to be the Heusler alloy layer is thereby formed.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: June 22, 2010
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno, Daisuke Miyauchi, Shinji Hara, Takahiko Machita
  • Patent number: 7738218
    Abstract: A magnetic detection element capable of maintaining the ?RA at a high level and reducing the magnetostriction by improving a material for a free magnetic layer, as well as a method for manufacturing the same, is provided. The free magnetic layer includes a laminate composed of a CoMnX alloy layer formed from a metal compound represented by a compositional formula CoaMnbXc (where X represents at least one of Ge, Ga, In, Si, Pb, Zn, and Sb and a+b+c=100 atomic percent) and a CoMnZ alloy layer formed from a metal compound represented by a compositional formula CodMneZf (where Z represents at least one of Sn and Al and d+e+f=100 atomic percent). In this manner, the magnetostriction of the free magnetic layer can be reduced.
    Type: Grant
    Filed: May 17, 2006
    Date of Patent: June 15, 2010
    Assignee: TDK Corporation
    Inventors: Yosuke Ide, Masamichi Saito, Masahiko Ishizone, Naoya Hasegawa
  • Patent number: 7733611
    Abstract: A magnetoresistance effect element comprises a free layer composed of a ferromagnetic layer, a pinned layer composed of a ferromagnetic layer, and a layer disposed between the free layer and the pinned layer and including at least one nano-contact portion disposed at least one portion between the free layer and the pinned layer. The nano-contact portion has a dimension, including at least one of a length in the layer lamination direction and a length in a direction normal to the layer lamination direction, being not more than Fermi length. The nano-contact portion is provided, in an inside portion thereof, with a magnetic wall composed of either one of Bloch magnetic wall, NĂ«el magnetic wall or a combination wall thereof.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: June 8, 2010
    Assignee: TDK Corporation
    Inventors: Isamu Sato, Rachid Sbiaa
  • Patent number: 7719799
    Abstract: A magnetoresistive element has a first magnetic layer and a second magnetic layer separate from each other, the first magnetic layer and the second magnetic layer each having a magnetization whose direction is substantially pinned, and a non-magnetic conductive layer formed in contact with the first magnetic layer and the second magnetic layer and electrically connecting the first and second magnetic layers, the non-magnetic conductive layer forming a path of spin-polarized electrons from one of the magnetic layer to the other magnetic layer, the non-magnetic conductive layer comprising a portion located between the first magnetic layer and the second magnetic layer, the portion being a sensing area.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: May 18, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Susumu Hashimoto, Hitoshi Iwasaki
  • Publication number: 20100118448
    Abstract: In one embodiment, a differential-type magnetic read head includes a differential-type magneto-resistive-effect film formed on a substrate, and a pair of electrodes for applying current in a direction perpendicular to a film plane of the film. The film includes a first and second stacked film, each having a pinned layer, an intermediate layer, and a free layer, with the second stacked film being formed on the first stacked film. A side face in a track width direction of the film is shaped to have an inflection point at an intermediate position in a thickness direction of the film, and the side face is shaped to be approximately vertical to the substrate in an upward direction of the substrate from the inflection point. Also, the side face is shaped to be gradually increased in track width as approaching the substrate in a downward direction of the substrate from the inflection point.
    Type: Application
    Filed: November 9, 2009
    Publication date: May 13, 2010
    Inventors: Kan Yasui, Masato Shiimoto, Takeshi Nakagawa, Hiroyuki Katada, Nobuo Yoshida, Hiroyuki Hoshiya
  • Patent number: 7712205
    Abstract: In a magnetic head manufacturing method, a floated surface of each block having plural magnetic head elements formed and arranged on a substrate is ground and lapped in a grinding/lapping step. The grinding/lapping step contains an angle adjusting step for adjusting the angle of the floated surface of the block with reference to a magnetic-head-element formed surface of a substrate and grinding the floated surface concerned, and a finishing lapping step of lapping the floated surface at an angle adjusted in the angle adjusting step.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: May 11, 2010
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshiaki Ito, Osamu Fukuroi, Hiroyasu Tuchiya, Kenji Kodaka
  • Patent number: 7710690
    Abstract: A magneto-resistance effect element can obtain a high output and makes it possible to stabilize magnetization in a magnetization free layer therein even if a sense current is caused to flow. The magneto-resistance effect element is provided with a magnetization free layer whose magnetization direction is variable, a magnetization pinned layer whose magnetization direction is pinned, and an intermediate layer provided between the magnetization free layer and the magnetization pinned layer, where when no external magnetic field is present and no current flows, the magnetization direction in the magnetization free layer is anti-parallel to the magnetization direction pinned in the magnetization pinned layer, an easy axis of magnetization in the magnetization free layer is parallel to the magnetization direction pinned in the magnetization pinned layer, and a sense current flows from the magnetization free layer to the magnetization pinned layer.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: May 4, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Hirofumi Morise
  • Patent number: 7698807
    Abstract: Formation of the magnetic sensor layers of a magnetic sensor are separated into at least two depositions to reduce the dimension of the sensor. The free layer portion of the sensor is deposited at a different process step than the pinned layer portion. The top of the free layer stack can be a tunnel barrier, the free layer, or part of the free layer. The free layer stack also may contain an in-stack bias layer. The longitudinal bias layer may be patterned in a separate processing step, which allows the stack containing the free layer to be effectively thinner and allow smaller track width dimensions.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: April 20, 2010
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Jeffrey Robinson Childress, Robert E. Fontana, Jr., Jeffrey S. Lille
  • Patent number: 7697244
    Abstract: A magnetic head in one embodiment includes first and second ferromagnetic shield layers, first and second nonmagnetic read-gap layers positioned between the first and second ferromagnetic shield layers, a sensor used in a current-in-plane (CIP) mode, first and second longitudinal bias layers electrically coupled with the sensor, and first and second conducting layers electrically coupled with the first and second longitudinal bias layers, respectively.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: April 13, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Tsann Lin
  • Patent number: 7697243
    Abstract: The determination of the strength of an in-plane magnetic field utilizing one or more magnetically-soft, ferromagnetic member, having a shape, size and material whereas a single magnetic vortex is formed at remanence in each ferromagnetic member. The preferred shape is a thin circle, or dot. Multiple ferromagnetic members can also be stacked on-top of each other and separated by a non-magnetic spacer. The resulting sensor is hysteresis free. The sensor's sensitivity, and magnetic saturation characteristics may be easily tuned by simply altering the material, size, shape, or a combination thereof to match the desired sensitivity and saturation characteristics. The sensor is self-resetting at remanence and therefore does not require any pinning techniques.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: April 13, 2010
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Valentyn Novosad, Kristen Buchanan
  • Patent number: 7697245
    Abstract: A spin-valve type magnetic head which has sufficiently high output is provided. In one embodiment, a structure in which high output coexists with high stability is achieved by letting a GMR-effect and a current-path-confinement effect manifest themselves at the same time in a GMR-screen layer consisting of a ferromagnetic metal spike-like part and a half-covering oxide layer.
    Type: Grant
    Filed: October 19, 2006
    Date of Patent: April 13, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hiroyuki Hoshiya, Katsumi Hoshino, Kenichi Meguro, Yo Sato, Hiroyuki Katada
  • Publication number: 20100079919
    Abstract: In a spin-torque oscillator, a first ferromagnetic layer, a non-magnetic layer and a second ferromagnetic layer are stacked. A pair of electrodes perpendicularly applies a current onto each plane of the first ferromagnetic layer, the non-magnetic layer and the second ferromagnetic layer. The current induces a precession of a magnetization of at least one of the first ferromagnetic layer and the second ferromagnetic layer. The at least one is formed by an in-plane magnetization film having a uniaxial magnetic anisotropy. A magnetic field generator generates a magnetic field to control a direction of the magnetization so that a non-linearity frequency shift of the precession by the uniaxial magnetic anisotropy cancels a non-linearity frequency shift of the precession by a demagnetizing field on the in-plane magnetization film.
    Type: Application
    Filed: September 8, 2009
    Publication date: April 1, 2010
    Inventors: Tazumi Nagasawa, Kiwamu Kudo, Koichi Mizushima, Rie Sato
  • Patent number: 7684160
    Abstract: A method and system for providing a magnetoresistive structure is disclosed. The magnetoresistive structure includes a pinned layer, a nonmagnetic spacer layer, a free layer, a specular layer, a barrier layer, and a capping layer. The spacer layer resides between the pinned layer and the free layer. The free layer is electrically conductive and resides between the specular layer and the nonmagnetic spacer layer. The specular layer is adjacent to the free layer and includes at least one of titanium oxide, yttrium oxide, hafnium oxide, magnesium oxide, aluminum oxide, nickel oxide, iron oxide, zirconium oxide, niobium oxide, and tantalum oxide. The barrier layer resides between the specular layer and the capping layer. The barrier layer is nonmagnetic and includes a first material. The capping layer includes a second material different from the first material.
    Type: Grant
    Filed: February 6, 2006
    Date of Patent: March 23, 2010
    Assignee: Western Digital (Fremont), LLC
    Inventors: Dustin Erickson, Chang-man Park, Shin Funada, Lena Miloslavsky
  • Patent number: 7683446
    Abstract: A magnetization direction in a magnetosensing layer (5b) is perturbed near the magnetic connection between a magnetic yoke (5) and the magnetosensing layer (5b). If the magnetization direction of a region in the magnetosensing layer (5b) facing a fixed layer which functions during read is not perturbed, reliability is improved. In this magnetometric sensor, a surface area S1 of fixed layers (43, 44) is made smaller than a surface area S2 of the magnetosensing layer (5b) so that, in the region of the magnetosensing layer (5b) facing the fixed layer, the magnetization direction is perturbed less than in the surrounding region and reliability during data read is improved.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: March 23, 2010
    Assignee: TDK Corporation
    Inventor: Keiji Koga
  • Patent number: 7672086
    Abstract: A method and system for providing a current confined magnetic element is disclosed. The method and system include providing a pinned layer, providing a nonmagnetic spacer layer, and providing a free layer. The nonmagnetic spacer layer resides between the pinned layer and the free layer. The method and system also include sputtering a current confinement layer. The current confinement layer includes an insulator and a conductor that are immiscible. The conductor forms a plurality of nano-dots in an insulating matrix. At least a portion of the plurality of nano-dots extends through the current confinement layer.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: March 2, 2010
    Assignee: Western Digital (Fremont), LLC
    Inventor: Hai Jiang
  • Patent number: 7672087
    Abstract: Provided is an MR effect element in which the magnetization of the pinned layer is stably fixed even after going through high temperature process. The MR effect element comprises: a non-magnetic intermediate layer; a pinned layer and a free layer stacked so as to sandwich the non-magnetic intermediate layer; an antiferromagnetic layer stacked to have a surface contact with the pinned layer, for fixing a magnetization of the pinned layer to a direction in-plane of the pinned layer and perpendicular to a track width direction; and hard bias layers provided on both sides in the track width direction of the free layer, for applying a bias field to the free layer, a product ?SĂ—? of a saturation magnetostriction constant ?S of the pinned layer and an internal stress ? on a cross-section perpendicular to a layer surface of the hard bias layer being negative.
    Type: Grant
    Filed: March 27, 2007
    Date of Patent: March 2, 2010
    Assignee: TDK Corporation
    Inventors: Takayasu Kanaya, Katsuki Kurihara, Tetsuya Kuwashima
  • Publication number: 20100033880
    Abstract: A multi-bit spin torque magnetic element that has a ferromagnetic pinned layer having a pinned magnetization orientation, a non-magnetic layer, and a ferromagnetic free layer having a magnetization orientation switchable among at least four directions, the at least four directions being defined by a physical shape of the free layer. The magnetic element has at least four distinct resistance states. Magnetic elements with at least eight magnetization directions are also provided.
    Type: Application
    Filed: October 21, 2008
    Publication date: February 11, 2010
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Dimitar V. Dimitrov, Zheng Gao, Xiaobin Wang
  • Patent number: 7650684
    Abstract: A method for fabricating a magnetic head including a spin valve sensor having a sensor layer stack that includes a pinned magnetic layer, a spacer layer formed on the pinned magnetic layer, and a free magnetic layer formed on the spacer layer. In a preferred embodiment the spacer layer is comprised of CuOx. The method includes the plasma smoothing of the upper surface of the pinned magnetic layer prior to depositing the spacer layer, and a preferred plasma gas is a mixture of argon and oxygen.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: January 26, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Wen-Yaung Lee, Tsann Lin, Danielle Mauri, Alexander Michael Zeltser
  • Patent number: 7639456
    Abstract: A current perpendicular to plane (CPP) sensor and method of manufacturing such a sensor that prevents current shunting at the sides of the barrier/spacer layer due to redeposited material. A first ion mill is performed to remove at least the free layer. A quick glancing ion mill can be performed to remove the small amount of redep that may have accumulated on the sides of the free layer and barrier/spacer layer. Then an insulation layer is deposited to protect the sides of the free layer/barrier layer during subsequent manufacturing which can include further ion milling to define the rest of the sensor and another glancing ion mill to remove the redep formed by the further ion milling. This results in a sensor having no current shunting at the sides of the sensor and having no damage to the sensor layers.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: December 29, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Ying Hong, Wipul Pemsiri Jayasekara
  • Publication number: 20090316308
    Abstract: A CPP giant magnetoresistive head includes lower and upper shield layers, and a giant magnetoresistive element disposed between the upper and lower shield layers and including a pinned magnetic layer, a free magnetic layer and a nonmagnetic layer disposed between the pinned magnetic layer and the free magnetic layer. In the CPP giant magnetoresistive head, the pinned magnetic layer extends to the rear of the nonmagnetic layer and the free magnetic layer in the height direction, and the dimension of the pinned magnetic layer in the height direction is larger than that in the track width direction. Also, the pinned magnetic layer comprises a magnetic material having a positive magnetostriction constant or a magnetic material having high coercive force, and the end of the pinned magnetic layer is exposed at a surface facing a recording medium.
    Type: Application
    Filed: August 27, 2009
    Publication date: December 24, 2009
    Inventors: Masamichi Saito, Yoshihiro Nishiyama, Yosuke Ide, Eiji Umetsu, Naoya Hasegawa, Yasuo Hayakawa
  • Patent number: 7633699
    Abstract: An apparatus includes a magnetically biased multilayer structure having a reference layer and a free layer separated by a spacer layer; a DC current source connected to the multilayer structure; an AC current source connected to the multilayer structure; and a phase detector for measuring a phase difference between an AC current and a voltage across the multilayer structure. A method performed by the apparatus is also provided.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: December 15, 2009
    Assignee: Seagate Technology LLC
    Inventors: Shehzaad Kaka, Mark William Covington, Nils Jan Gokemeijer, Michael Allen Seigler
  • Patent number: 7633132
    Abstract: A magnetic sensor comprises a substrate, magnetoresistive element of a spin-valve type, a bias magnetic layer (or a permanent magnet film), and a protective film, wherein the bias magnetic layer is connected with both ends of the magnetoresistive element and the upper surface thereof is entirely covered with the lower surface of the magnetoresistive element at both ends. Herein, distances between the side surfaces of the both ends of the magnetoresistive element and the side surfaces of the bias magnetic layer viewed from the protective film do not exceed 3 ?m. In addition, a part of the bias magnetic layer can be covered with both ends of the magnetoresistive element, and an intermediate layer is arranged in relation to the magnetoresistive element, bias magnetic layer, and protective film so as to entirely cover the upper surface of the bias magnetic layer.
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: December 15, 2009
    Assignee: Yamaha Corporation
    Inventors: Yukio Wakui, Susumu Yoshida, Kokichi Aiso
  • Patent number: 7623323
    Abstract: Embodiments of the invention provide a reading head structure that ensures a stable magnetic moment of a pinned layer against a great external magnetic field, and minimizes the pinned-layer damage occurring during air-bearing surface machining. In one embodiment, a magnetoresistive head is based on a spin-valve effect and has free layers, a stacked-type pinned layer, and an electroconductive nonmagnetic spacer layer positioned between the free layers and the stacked-type pinned layer. The stacked-type pinned layer includes three ferromagnetic films, and antiferromagnetic coupling films interposed between the ferromagnetic films. Of these ferromagnetic films, the first two films have a high coercivity and a high resistivity. The third ferromagnetic film is made of a material that gives a great magnetoresistive effect. The sum of the magnetic moments generated from the stacked-type pinned layer is substantially zero.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: November 24, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Koichi Nishioka, Shuichi Kojima, Koji Kataoka, Takayoshi Ohtsu
  • Patent number: 7621038
    Abstract: A method for fabricating a three terminal magnetic (TTM) sensor of a magnetic head according to one embodiment includes fabricating a P-type semiconductor material; fabricating an N-type semiconductor material at an upper surface of a portion of said P-type semiconductor material; fabricating a spin valve structure upon said N-type semiconductor material; engaging a collector lead to said P-type semiconductor material; engaging a base lead to said N-type semiconductor material; and engaging an emitter lead to said spin valve structure.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: November 24, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Jeffrey S. Lille
  • Patent number: 7612969
    Abstract: A magnetic memory device includes a pinning layer, a pinned layer, an insulation layer, which are sequentially stacked on a semiconductor substrate. The magnetic memory device further includes a free layer disposed on the insulation layer, a capping layer disposed on the free layer and an MR (magnetoresistance) enhancing layer interposed between the free layer and the capping layer. The MR enhancing layer is formed of at least one anti-ferromagnetic material.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: November 3, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Se-Chung Oh, Jang-Eun Lee, Hyun-Jo Kim, Kyung-Tae Nam, Jun-Ho Jeong
  • Patent number: 7603763
    Abstract: A method for manufacturing a magnetoresistive multilayer film. An antiferromagnetic layer, a pinned-magnetization layer, a nonmagnetic spacer layer and a free-magnetization layer are laminated on a substrate in this order. A film for the antiferromagnetic layer is deposited by a sputtering process as oxygen gas is added to a gas for sputtering. A film for an extra layer interposed between the substrate and the antiferromagnetic layer is deposited by a sputtering process as oxygen gas is added to a gas for sputtering. A film for the antiferromagnetic layer is deposited by a sputtering process with a gas mixture of argon and another gas of larger atomic number than argon.
    Type: Grant
    Filed: October 18, 2004
    Date of Patent: October 20, 2009
    Assignee: Canon Anelva Corporation
    Inventors: David Djulianto Djayaprawira, Koji Tsunekawa, Motonobu Nagai
  • Publication number: 20090257153
    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.
    Type: Application
    Filed: April 10, 2008
    Publication date: October 15, 2009
    Inventor: Yue Liu
  • Patent number: 7602591
    Abstract: A magnetoresistive element is provided as a spin valve having a synthetic free layer. More specifically, the synthetic free layer includes a low perpendicular anisotropy layer that is separated from a high perpendicular anisotropy layer by a spacer. Thus, the high anisotropy material introduces an out-of-plane component by exchange coupling. The high perpendicular anisotropy material also has low spin polarization. Further, the low anisotropy material positioned closer to the pinned layer has a high spin polarization. As a result, the magnetization of the low anisotropy material is re-oriented from an in-plane direction to an out-of-plane direction. Accordingly, the overall free layer perpendicular anisotropy can be made small as a result of the low anisotropy material and the high anisotropy material. Adjusting the thickness of these layers, as well as the spacer therebetween, can further lower the anisotropy and thus further increase the sensitivity.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: October 13, 2009
    Assignee: TDK Corporation
    Inventors: Rachid Sbiaa, Isamu Sato, Haruyuki Morita
  • Publication number: 20090244790
    Abstract: An magnetoresistive element includes: an underlayer made of a nitride; a pinning layer made of an antiferromagnetic layer overlaid on the underlayer, the pinning layer having the close-packed surface in the (111) surface of crystal, the pinning layer setting the (002) surface of crystal in parallel with the surface of the underlayer; a reference layer overlaid on the pinning layer, the reference layer having the magnetization fixed in a predetermined direction based on the exchange coupling with the pinning layer; a nonmagnetic layer overlaid on the reference layer, the nonmagnetic layer made of a nonmagnetic material; and a free layer overlaid on the nonmagnetic layer, the free layer made of a ferromagnetic material, the free layer enabling a change in the direction of the magnetization under the influence of an external magnetic field.
    Type: Application
    Filed: March 23, 2009
    Publication date: October 1, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Takahiro Ibusuki, Masashige Sato, Shinjiro Umehara
  • Publication number: 20090244789
    Abstract: The method and system for providing a magnetoresistive device are disclosed. The magnetoresistive device is formed from a plurality of magnetoresistive layer. The method and system include providing a mask. The mask covers a first portion of the magnetoresistive element layers in at least one device area. The magnetoresistive element(s) are defined using the mask. The method and system include depositing hard bias layer(s). The method and system also include providing a hard bias capping structure on the hard bias layer(s). The hard bias capping structure includes a first protective layer and a planarization stop layer. The first protective layer resides between the planarization stop layer and the hard bias layer(s). The method and system also include performing a planarization. The planarization stop layer is configured for the planarization.
    Type: Application
    Filed: April 1, 2008
    Publication date: October 1, 2009
    Applicant: Westem Digital (Fremont), LLC
    Inventors: Liubo Hong, Honglin Zhu
  • Patent number: 7593195
    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: December 12, 2006
    Date of Patent: September 22, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7589939
    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: September 28, 2005
    Date of Patent: September 15, 2009
    Assignee: Yamaha Corporation
    Inventors: Yukio Wakul, Masayoshi Omura
  • Patent number: 7583480
    Abstract: A magnetoresistance effect element includes a free layer as a first ferromagnetic layer, a pinned layer as a second ferromagnetic layer, and at least one nano-junction provided between the free layer and the pinned layer. The nano-junction contains at least one non-metal selected from the group consisting of oxygen, nitrogen, sulfur and chlorine. Preferably, the material for forming the nano-junction is a ferromagnetic metal selected from the group consisting of Fe, Ni, Co, NiFe, CoFe and CoFeNi or a halfmetal selected from the group consisting of NiFeSb, NiMnSb, PtMnSb and MnSb.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: September 1, 2009
    Assignee: TDK Corporation
    Inventors: Rachid Sbiaa, Isamu Sato
  • Publication number: 20090207533
    Abstract: A magnetic field detecting element includes: first and second free layers whose magnetization directions change in accordance with an external magnetic field; a spacer layer that is sandwiched between the first and second free layers; a first exchange coupling transmitting layer that is located adjacent to a surface of first free layer, the surface of first free layer 53 being opposite to a surface of the first free layer which is located adjacent to the spacer layer; a first pinned layer which is provided such that the first pinned layer and the first free layer sandwich the first exchange coupling transmitting layer and which is exchange-coupled to first free layer via the first exchange coupling transmitting layer; a second exchange coupling transmitting layer that is located adjacent to a surface of the second free layer, the surface of the second free layer being opposite to a surface of the second free layer which is located adjacent to the spacer layer; a second pinned layer which is provided such that
    Type: Application
    Filed: February 19, 2008
    Publication date: August 20, 2009
    Inventor: Koji SHIMAZAWA
  • Patent number: 7573685
    Abstract: A magnetoresistive sensor having a Ta cap layer with nitrogen added in situ during deposition. The nitrogen in the cap layer can be formed by depositing a Ta cap layer in a sputter deposition chamber having a small amount of nitrogen in an Ar atmosphere. The resulting nitrogenated cap layer exhibits reduced specular scattering, which results in improved magnetic performance of the magnetoresistive sensor.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: August 11, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Wen-yaung Lee, Thomas E. Shatz, Dulip Ajantha Welipitiya, Brian R. York
  • Patent number: 7564657
    Abstract: Provided are a magnetoresistive device capable of obtaining a larger amount of resistance change and responding to a higher recording density and a thin film magnetic head comprising the magnetoresistive device. A first magnetization fixed film and a second magnetization fixed film have magnetization directions antiparallel to each other, and the second magnetization fixed film farther from a magnetization free layer is made of, for example, a material including at least one selected from the group consisting of tantalum (Ta), chromium (Cr) and vanadium (V), and has a bulk scattering coefficient of 0.25 or less. Thereby, a bulk scattering effect by the second magnetization fixed film which has a function of canceling out the amount of resistance change between the magnetization free layer and the first magnetization fixed film can be prevented, and a magnetoresistive ratio ?R/R can be improved, and recorded magnetic information with a higher recording density can be read out.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: July 21, 2009
    Assignee: TDk Corporation
    Inventors: Daisuke Miyauchi, Tomohito Mizuno
  • Publication number: 20090180218
    Abstract: An information storage device includes a magnetic layer configured to store information, a first and second conductive layer. The first conductive layer contacts a first end of the magnetic layer. The second conductive layer contacts a second end of the magnetic layer. The magnetic layer includes first and second pinning regions at which magnetic domain walls are pinned. The widths of the magnetic layer at the first and second pinning regions are different.
    Type: Application
    Filed: June 10, 2008
    Publication date: July 16, 2009
    Inventors: Ji-young Bae, Kwang-seok Kim, Mathias Klaui
  • Patent number: 7561384
    Abstract: A high output magneto-resistive sensor is provided by suppressing leftover resist mask after lift-off and generation of a fence, and by making it easy to remove the redepositions deposited on the side wall in the track width direction or on the side wall in the sensor height direction of the magnetoresistive film. As a means to solve a fence and lift-off leftover of a resist in a process for forming a track and a process for forming a sensor height, a stopper layer is provided on the magnetoresistive film and the stopper layer on the refill film, and performing lift-off by CMP. By using a metallic material which has a small CMP polishing rate for at least the first stopper layer, the magnetoresistive film and the first stopper layer can be etched simultaneously and a pattern formed. As a result, decrease of the height of the resist mask by RIE can be suppressed and lift-off leftover can be prevented.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: July 14, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Masahiro Osugi, Taku Shintani, Katsuro Watanabe, Nobuo Yoshida
  • Publication number: 20090168266
    Abstract: Embodiments of the present invention provide a practical magneto-resistive effect element for CPP-GMR, which exhibits appropriate resistance-area-product and high magnetoresistance change ratio, and meets the demand for a narrow read gap. Certain embodiments of a magneto-resistive effect element in accordance with the present invention include a pinned ferromagnetic layer containing a first ferromagnetic film having a magnetization direction fixed in one direction, a free ferromagnetic layer containing a second ferromagnetic film having a magnetization direction varying in response to an external magnetic field, an intermediate layer provided between the pinned ferromagnetic layer and the free ferromagnetic layer, and a current confinement layer for confining a current. At least one of the pinned ferromagnetic layer or the free ferromagnetic layer includes a highly spin polarized layer.
    Type: Application
    Filed: November 21, 2008
    Publication date: July 2, 2009
    Inventors: Yo Sato, Katsumi Hoshino, Hiroyuki Hoshiya
  • Patent number: 7554774
    Abstract: In a magnetic resistance device, and a method of manufacturing the same, the magnetic resistance device includes a pinning layer, a pinned layer, a nonmagnetic layer, and a free layer stacked on one another, at least one of the pinned layer and the free layer being formed of an intermetallic compound.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: June 30, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Tae-wan Kim, Kee-won Kim, Soon-ju Kwon, Sang-jin Park
  • Publication number: 20090161266
    Abstract: A high performance TMR element is fabricated by inserting an oxygen surfactant layer (OSL) between a pinned layer and AlOx tunnel barrier layer in a bottom spin valve configuration. The pinned layer preferably has a SyAP configuration with an outer pinned layer, a Ru coupling layer, and an inner pinned layer comprised of CoFeXBY/CoFeZ wherein x=0 to 70 atomic %, y=0 to 30 atomic %, and z=0 to 100 atomic %. The OSL is formed by treating the CoFeZ layer with oxygen plasma. The AlOx tunnel barrier has improved uniformity of about 2% across a 6 inch wafer and can be formed from an Al layer as thin as 5 Angstroms. As a result, the Hin value can be decreased by ? to about 32 Oe. A dR/R of 25% and a RA of 3 ohm-cm2 have been achieved for TMR read head applications.
    Type: Application
    Filed: January 27, 2009
    Publication date: June 25, 2009
    Inventors: Hui-Chuan Wang, Tong Zhao, Min Li, Kunliang Zhang
  • Publication number: 20090154032
    Abstract: A magnetoresistive sensor having a hard bias structure that provides improved bias field robustness. The sensor includes a nitrogenated hard bias layer and a seed layer that include a nitrogenated NiTa layer and a layer of Ru. The seed layer can also include a layer of CrMn disposed between the layer of NiTa and the layer of Ru. The novel seed structure allows a nitrogenated hard bias layer to be used, while maintaining a high magnetic coercivity of the hard bias layer.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 18, 2009
    Inventor: James Mac Freitag
  • Publication number: 20090141408
    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: Application
    Filed: February 6, 2009
    Publication date: June 4, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7538987
    Abstract: A CPP spin-valve element formed on a substrate including a free layer structure including at least one ferromagnetic layer and a pinned layer structure including at least one ferromagnetic layer. The free layer is magnetically softer than the pinned layer. A thin non-magnetic spacer layer structure configured to separate the free layer and the pinned layer is provided in order to prevent a magnetic coupling between the free and pinned layer structures, and to allow an electric current to go there through. At least two current-confining (CC) layer structures including at least two parts having significantly different current conductivities are incorporated therein.
    Type: Grant
    Filed: July 3, 2003
    Date of Patent: May 26, 2009
    Assignees: University of Alabama, Fujitsu, Ltd.
    Inventors: Hideo Fujiwara, Keiichi Nagasaka, Tong Zhao, William H. Butler, Julian Velev, Amrit Bandyopadhyay
  • Patent number: 7536772
    Abstract: A method is given for the manufacture of a bottom spin valve (BSV) spin filter spin valve (SFSV) type read sensor. The sensor has a composite, ultra-thin (<20 Angstroms) laminated free layer formed as a Cu high conductance layer (HCL) between two layers of CoFe. A second HCL is formed as a layer of Ru on the composite free layer. By adjusting the thicknesses of the two HCL's, the free layer will have low coercivity and tunable magnetostriction. The sensor is capable of reading densities exceeding 60 Gb/in2.
    Type: Grant
    Filed: November 8, 2005
    Date of Patent: May 26, 2009
    Assignee: Headway Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Patent number: 7535682
    Abstract: A magneto-resistance element according to the present invention has a pinned layer whose magnetization direction is fixed; a free layer whose magnetization direction varies in accordance with an external magnetic field; and a nonmagnetic spacer layer that is arranged between the pinned layer and the free layer, at least the pinned layer or the free layer includes a layer having Heusler alloy represented by composition formula X2YZ (where X is a precious metal element, Y is a transition metal of Mn, V, or Ti group, Z is an element from group III to group V), and a part of composition X is replaced with Co, and an atomic composition ratio of Co in composition X is from 0.5 to 0.85.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: May 19, 2009
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yoshihiro Tsuchiya, Tomohito Mizuno
  • Patent number: 7530160
    Abstract: A method for manufacturing a magnetoresistive sensor having improved free layer biasing and track width control. The method includes forming a ferromagnetic pinned layer, and depositing a ferromagnetic film thereover. A layer of Ta is deposited over the ferromagnetic film and a mask is formed over an active sensor area. A reactive ion etch process is performed to remove selected portions of said Ta layer. An etch is then performed to remove selected portions of the ferromagnetic film in unmasked areas and a ferromagnetic refill material is deposited.
    Type: Grant
    Filed: September 5, 2007
    Date of Patent: May 12, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal Singh Gill
  • Patent number: 7525772
    Abstract: A magnetoresistive device includes a magnetoresistive film and a pair of electrodes for applying a sense current substantially perpendicularly to the magnetoresistive film. The magnetoresistive film includes a magnetization pinned film including a first ferromagnetic layer having a magnetization direction substantially pinned in one direction, a magnetization free film including a second ferromagnetic layer whose magnetization direction changes in accordance with an external magnetic field applied thereto, an intermediate layer formed between the magnetization pinned film and the magnetization free film and having an insulating film and a metal conduction portion extending in the film thickness direction of the insulating film, and a layer containing an electrovalent or covalent compound formed near the metal conduction portion.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: April 28, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Koui, Takashi Tateyama, legal representative, Tomomi Funayama, Koichi Kubo, Hitoshi Iwasaki, Hideaki Fukuzawa, Kohichi Tateyama
  • Patent number: 7525771
    Abstract: A method for evaluating a magnetized state of a pinned layer of a magnetoresistive spin-valve element used, together with a recording element, in a magnetic head, is provided. The method includes the steps of (a) supplying a first alternating current to the recording element, while supplying a second current for generating a magnetic field to the spin-valve element, the direction of the magnetic field generated by the second current being opposite to a prescribed direction of magnetization of the pinned layer adjacent to an antiferromagnetic layer; and (b) determining whether the magnetization of the pinned layer is inverted toward said direction opposite to the prescribed direction.
    Type: Grant
    Filed: August 18, 2005
    Date of Patent: April 28, 2009
    Assignee: Fujitsu Limited
    Inventor: Takeshi Iwase
  • Patent number: 7522389
    Abstract: A magnetoresistance effect element is composed of a first ferromagnetic layer, a second ferromagnetic layer, and at least one nano-contact portion formed between the first and second ferromagnetic layers, which are formed on the same plane on a substrate. The nano-contact portion has a maximum dimension of not more than Fermi length of a material constituting the nano-contact portion. A permanent magnet layer or in-stack bias layer may be further formed on the first and/or second ferromagnetic layer.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: April 21, 2009
    Assignee: TDK Corporation
    Inventors: Rachid Sbiaa, Isamu Sato