Three Or More Magnetic Layers On One Substrate Side Patents (Class 428/828.1)
  • Patent number: 11189313
    Abstract: A magnetic recording medium includes a substrate, an underlayer provided above the substrate, and a magnetic layer provided on and in contact with the underlayer. The underlayer includes a compound represented by a general formula MgO(1-x), where x falls within a range of 0.07 to 0.25. The magnetic layer includes an alloy having a L10 structure, and the alloy having the L10 structure includes one or more elements selected from a group consisting of Al, Si, Ga, and Ge.
    Type: Grant
    Filed: January 5, 2021
    Date of Patent: November 30, 2021
    Assignee: SHOWA DENKO K.K.
    Inventors: Koichi Nagasaka, Takayuki Fukushima, Lei Zhang, Chen Xu, Hisato Shibata, Takehiro Yamaguchi, Hiroshi Koyanagi, Yuji Umemoto
  • Patent number: 11088200
    Abstract: The invention comprises a novel composite seed layer with lattice-matched crystalline structure so that an excellent epitaxial growth of magnetic pinning layer along its FCC (111) orientation can be achieved, resulting in a significant enhancement of PMA for perpendicular spin-transfer-torque magnetic-random-access memory (pSTT-MRAM) using perpendicular magnetoresistive elements as basic memory cells which potentially replace the conventional semiconductor memory used in electronic chips, especially mobile chips for power saving and non-volatility.
    Type: Grant
    Filed: February 10, 2020
    Date of Patent: August 10, 2021
    Inventor: Rongfu Xiao
  • Patent number: 11081154
    Abstract: The present invention discloses an enhanced synthetic antiferromagnetic (eSAF) element with a very strong RKKY coupling comprising a magnetic pinning layer having a face-center-cubic (fcc) crystalline structure and a magnetic reference layer having a body-center-cubic (bcc) crystalline structure which are antiferromagnetically coupled by a composite non-magnetic spacer (CnmS) containing a bi-layer of (Ru, Rh or Ir)/Cr or tri-layer of (Ru, Rh, or Ir)/(W, Mo, or V)/Cr. With such eSAF, a strong magnetic pinning element is formed which can be used to make various thin STT-MRAM film stacks with good thermal and magnetic stability while maintaining high TMR value.
    Type: Grant
    Filed: January 27, 2020
    Date of Patent: August 3, 2021
    Inventors: Rongfu Xiao, Yimin Guo, Jun Chen
  • Patent number: 11025200
    Abstract: A magnetic structure is provided. The magnetic structure may have a first magnetic layer with a first magnetization direction, a second magnetic layer with a second magnetization direction and a coupling layer interposed between the first and second magnetic layers. The coupling layer may include at least one non-magnetic element and at least one magnetic element. The atomic ratio of the at least one non-magnetic element to the at least one magnetic element is (100?x):x, where x is an atomic concentration parameter. Atomic concentration parameter, x, may cause the first magnetic layer to be non-collinearly coupled to the second magnetic layer such that, in the absence of external magnetic field, the first magnetization direction is oriented at a non-collinear angle relative to the second magnetization direction.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: June 1, 2021
    Inventors: Zachary Raymond Nunn, Erol Girt
  • Patent number: 10460755
    Abstract: Apparatus for recording data and method for making the same. In accordance with some embodiments, a recording layer is supported by a substrate. The recording layer has a granular magnetic recording layer with a first oxide content, a continuous magnetic recording layer with nominally no oxide content, and an oxide gradient layer disposed between the respective granular magnetic recording layer and the continuous magnetic recording layer. The oxide gradient layer has a second oxide content less than the first oxide content of the granular layer.
    Type: Grant
    Filed: October 16, 2013
    Date of Patent: October 29, 2019
    Assignee: Seagate Technology LLC
    Inventors: Pengcheng Li, Bin Lu, Thomas P. Nolan, Li-Lien Lee, Jai-Young Kim
  • Patent number: 10424724
    Abstract: According to one embodiment, a magnetic element includes a first member and a first magnetic portion. The first member includes a first region, a second region, and a third region positioned between the first region and the second region in a first direction. The first region includes at least one first element selected from the group consisting of Au, Ir, Al, Ta, TaN, W, Hf, Pt, and Pd. The second region includes at least one second element selected from the group. The third region includes at least one third element selected from the group. A concentration of the third element in the third region is lower than a concentration of the first element in the first region and lower than a concentration of the second element in the second region. A direction from the first region toward the first magnetic portion is aligned with a second direction.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: September 24, 2019
    Assignee: Toshiba Memory Corporation
    Inventors: Nobuyuki Umetsu, Tsuyoshi Kondo, Yasuaki Ootera, Takuya Shimada, Michael Arnaud Quinsat, Masaki Kado, Susumu Hashimoto, Shiho Nakamura
  • Patent number: 10210894
    Abstract: According to one embodiment, a magnetic recording medium includes a first layer and a second layer. The first layer includes a first magnetic region, a second magnetic region, and a nonmagnetic region provided between the first and second magnetic regions. A direction from the second magnetic region toward the first magnetic region is along a first direction. The second layer includes third, fourth, and fifth magnetic regions. At least a portion of the fifth magnetic region is provided between the third and fourth magnetic regions. The third magnetic region overlaps the first magnetic region in a second direction crossing the first direction. The fourth magnetic region overlaps the second magnetic region in the second direction. The fifth magnetic region overlaps the nonmagnetic region in the second direction. An easy magnetization axis of each of the first to fifth magnetic regions is aligned with the second direction.
    Type: Grant
    Filed: February 15, 2018
    Date of Patent: February 19, 2019
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Suto, Taro Kanao, Tazumi Nagasawa, Rie Sato, Koichi Mizushima
  • Patent number: 10199574
    Abstract: A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: February 5, 2019
    Assignee: Everspin Technologies, Inc.
    Inventors: Renu Whig, Jijun Sun, Nicholas Rizzo, Jon Slaughter, Dimitri Houssameddine, Frederick Mancoff
  • Patent number: 10056103
    Abstract: A method of manufacturing a magnetic recording medium, includes at least: forming an orientation control layer 3 that controls orientation of an immediately above layer thereof on a non-magnetic substrate 1; and forming a perpendicular magnetic layer 4 in which an easy axis of magnetization is mainly perpendicularly orientated to the non-magnetic substrate 1, in which the forming of the orientation control layer 3 includes forming a granular layer having a granular structure that includes Ru or a material in which Ru is a main component and an oxide having a melting point which is greater than or equal to 450° C. and less than or equal to 1000° C., by a sputtering method, and the forming of the perpendicular magnetic layer 4 includes growing crystal grains to form columnar crystals that are continuous in a thickness direction together with crystal grains that form the orientation control layer 3.
    Type: Grant
    Filed: January 22, 2014
    Date of Patent: August 21, 2018
    Assignee: SHOWA DENKO K.K.
    Inventors: Ken Inoue, Gohei Kurokawa, Haruhisa Ohashi
  • Patent number: 9966095
    Abstract: A magnetic media for magnetic data recording having reduced signal noise. The magnetic media includes a magnetic recording layer that has first, second and third portions. The first portion at the bottom of the magnetic recording layer includes an oxide and has a high anisotropy field. The third portion, located at the top of the magnetic recording layer has a low anisotropy field and does not include an oxide. The second portion, located between the first and third portions has an anisotropy field that is between that of the first and third magnetic portions. The second portion includes a thin layer of a material that has an extremely low anisotropy field that is located within a material having a higher magnetic anisotropy.
    Type: Grant
    Filed: August 2, 2016
    Date of Patent: May 8, 2018
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Shun Tonooka, Masayoshi Shimizu, Maki Maeda, Kiwamu Tanahashi
  • Patent number: 9934808
    Abstract: According to one embodiment, a magnetic recording medium includes: a substrate; and a magnetic recording layer structure formed above the substrate. The magnetic recording layer structure includes five or more magnetic recording layers and four or more nonmagnetic exchange coupling layers, where the magnetic recording layers and the nonmagnetic exchange coupling layers are arranged in an alternating pattern, and where the magnetic recording layers are separated from each other by least one of the nonmagnetic exchange coupling layers. The magnetic recording layer positioned closest to the substrate has each of the following: an average magnetic grain pitch of about 8.3 nm or less, a magnetic anisotropy field (Hk) value of greater than or equal to about 20 kOe, and a thickness that is about 40% of a total thickness of the magnetic recording layer structure.
    Type: Grant
    Filed: March 11, 2015
    Date of Patent: April 3, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventor: Yoshihiro Ikeda
  • Patent number: 9837483
    Abstract: An electrical device includes a current transport layer made of an anomalous Hall material. The electrical device also includes a first ferromagnetic island in physical contact with the current transport layer and a second ferromagnetic island in physical contact with the current transport layer, the second ferromagnetic island oriented with respect to the first ferromagnetic island such as to concentrate a magnetic field, generated by current flow along a conducting surface of the anomalous Hall material, over the first ferromagnetic island and the second ferromagnetic island.
    Type: Grant
    Filed: January 12, 2017
    Date of Patent: December 5, 2017
    Assignee: The Board of Trustees of the University of Illinois
    Inventors: Matthew J. Gilbert, Timothy M. Philip, Daniel Somerset Green
  • Patent number: 9824711
    Abstract: A soft underlayer (SUL) and methods for making an SUL are provided, the SUL having characteristics that make it compatible with the high temperature requirements associated with heat-assisted magnetic recording (HAMR) media growth and writing, e.g., temperatures greater than 500° C. The SUL may have a high crystallization temperature of greater than 450° C. and a high Curie temperature greater than 300° C., for example. Additionally, the SUL can maintain a saturation magnetization value greater than, e.g., 9 kGauss, at such high temperatures, thereby having the ability to remain amorphous at temperatures up to, e.g., 650° C., and exhibiting a relatively flat integrated noise profile from approximately 300° C. to 650° C. Further still, a spacer layer material is chosen such that inter-diffusion does not occur at these high temperatures.
    Type: Grant
    Filed: June 25, 2014
    Date of Patent: November 21, 2017
    Assignee: WD Media, LLC
    Inventors: Debashish Tripathy, Antony Ajan, Tomoko Seki, Gerardo A. Bertero
  • Patent number: 9734857
    Abstract: A stack including a crystallographic orientation interlayer, a magnetic zero layer disposed on the interlayer, and a magnetic recording layer disposed on the magnetic zero layer is disclosed. The magnetic zero layer is non-magnetic or has a saturation magnetic flux density (Bs) less than about 100 emu/cc. The magnetic zero layer and the magnetic layer include grains surrounded by a non-magnetic segregant. The magnetic zero layer provides a coherent interface between the interlayer and the magnetic layer with a lattice mismatch less than about 4%.
    Type: Grant
    Filed: July 24, 2015
    Date of Patent: August 15, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Jai-Young Kim, Thomas P. Nolan, Kyongha Kang, Shoutao Wang, Vincent D. Nguyen, Abebe Hailu, Charles C. Chen
  • Patent number: 9666221
    Abstract: An apparatus may include a first magnetic layer, a first exchange break layer formed on the first magnetic layer, a second magnetic layer formed on the first exchange break layer, a second exchange break layer formed on the second magnetic layer, and a third magnetic layer formed on the second exchange break layer. The first magnetic layer has a first magnetic anisotropy energy, Hk1, the second magnetic layer has a second magnetic anisotropy energy, Hk2, and the third magnetic layer has a third magnetic anisotropy energy, Hk3. In some embodiments, Hk1?Hk2 is less than Hk2?Hk3. In some embodiments, the apparatus may be a perpendicular magnetic recording medium.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: May 30, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Thomas P. Nolan, Hans Richter
  • Patent number: 9542968
    Abstract: FePt-based heat assisted magnetic recording (HAMR) media comprising a thick granular FePt:C magnetic recording layer capable of maintaining a single layer film having desirable magnetic properties. According to one embodiment, the thick granular FePt:C magnetic recording layer comprises a plurality of carbon doped FePt alloy columnar grains, where the plurality of carbon doped FePt alloy columnar grains comprise a carbon gradient along the thickness of the hard magnetic recording layer.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: January 10, 2017
    Assignee: WD MEDIA, LLC
    Inventors: Hua Yuan, Alexander S. Chernyshov, B. Ramamurthy Acharya
  • Patent number: 9406327
    Abstract: In one embodiment, a magnetic storage device includes at least one microwave assisted magnetic recording (MAMR) head, each MAMR head including a spin torque oscillator (STO), a magnetic recording medium, a drive mechanism for passing the magnetic medium over the at least one MAMR head, and a controller electrically coupled to the at least one MAMR head for controlling operation of the at least one MAMR head, wherein the magnetic recording medium includes a recording layer positioned directly or indirectly above a substrate and an assist layer positioned above the recording layer, wherein the recording layer includes at least Co, Pt, and an oxide or oxygen, wherein the assist layer is positioned closer to the at least one MAMR head and includes at least Co and Pt, and wherein at least a portion of the recording layer has a smaller anisotropic magnetic field than the assist layer.
    Type: Grant
    Filed: August 30, 2013
    Date of Patent: August 2, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Tatsuya Hinoue, Ichiro Tamai, Hiroaki Nemoto
  • Patent number: 9349404
    Abstract: [Problem] A perpendicular magnetic disk with an improved SNR and an increased recording density by further improving crystal orientation of a preliminary ground layer formed of an Ni-base alloy is provided. [Solution] A typical structure of the perpendicular magnetic disk according to the present invention includes, on a base 110, a soft magnetic layer 130, a Ta alloy layer 140 provided on the soft magnetic layer 130, an Ni alloy layer 142 provided on the Ta alloy layer 140, a ground layer 150 provided on the Ni alloy layer 142 and having Ru as a main component, and a granular magnetic layer 160 provided on the ground layer 150. The Ta alloy layer 140 is a layer containing 10 atomic percent or more and 45 atomic percent or less Ta and having amorphous and soft magnetic properties.
    Type: Grant
    Filed: May 31, 2011
    Date of Patent: May 24, 2016
    Assignee: WD Media (Singapore) PTE. LTD
    Inventors: Teiichiro Umezawa, Kazuaki Sakamoto
  • Patent number: 9263189
    Abstract: An apparatus for storing electrical energy comprising at least: a first multilayer section; a second multilayer section disposed above the first multilayer section; and a spacer layer disposed between the first and second multilayer sections and comprising a dielectric material, wherein each of the first and second multilayer sections comprising a pinned magnetic layer having a fixed magnetization direction, a free magnetic layer having a reversible magnetization direction, and an isolative layer disposed between the pinned and free magnetic layers, the pinned and free magnetic layers are substantially anti-ferromagnetically exchange coupled to each other through the isolative layer; and wherein the pinned magnetic layers of the first and second multilayer sections are electrically coupled in parallel with each other, and the free magnetic layers of the first and second multilayer sections are electrically coupled in parallel with each other.
    Type: Grant
    Filed: April 23, 2014
    Date of Patent: February 16, 2016
    Inventor: Alexander Mikhailovich Shukh
  • Patent number: 9224411
    Abstract: An apparatus includes a first magnetic layer including a plurality of grains. The first magnetic layer has a first anisotropy value. The apparatus also includes a second magnetic layer including a plurality of grains. The second magnetic layer has a second anisotropy value that is different than the first anisotropy value. The apparatus also includes an exchange tuning layer including a plurality of grains and located between the first and second magnetic layers. The exchange tuning layer has stronger inter-granular exchange coupling than the first and second magnetic layers. The exchange tuning layer has an anisotropy value less than the first and second anisotropy values.
    Type: Grant
    Filed: June 11, 2013
    Date of Patent: December 29, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Yingguo Peng
  • Patent number: 9142240
    Abstract: An apparatus may include a first magnetic layer, a first exchange break layer formed on the first magnetic layer, a second magnetic layer formed on the first exchange break layer, a second exchange break layer formed on the second magnetic layer, and a third magnetic layer formed on the second exchange break layer. The first magnetic layer has a first magnetic anisotropy energy, Hk1, the second magnetic layer has a second magnetic anisotropy energy, Hk2, and the third magnetic layer has a third magnetic anisotropy energy, Hk3. In some embodiments, Hk1?Hk2 is less than Hk2?Hk3. In some embodiments, the apparatus may be a perpendicular magnetic recording medium.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: September 22, 2015
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Thomas Patrick Nolan, Hans Jürgen Richter
  • Patent number: 9129635
    Abstract: There are provided a magnetic recording medium and a magnetic memory device capable of implementing high recording density, in the case of using a microwave assisted magnetic recording (MAMR) scheme. In a magnetic memory device including a magnetic recording medium having a recording film with three or more layers, a recording magnetic pole generating a recording magnetic field, an opposed magnetic pole, a high frequency magnetic field generating element generating a microwave for recording assist, and a magnetic reproduction element, an anisotropic field of a first layer which is a top layer of the recording film is larger than 20 kOe.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: September 8, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Fukuda, Yoshihiro Shiroishi
  • Patent number: 9059399
    Abstract: A mechanism is provided for a spin torque transfer random access memory device. A reference layer is disposed on a seed layer. A tunnel barrier is disposed on the reference layer. A free layer is disposed on the tunnel barrier. A cap layer is disposed on the free layer. The free layer includes a magnetic layer and a metal oxide layer, in which the magnetic layer is disposed on the tunnel barrier and the metal oxide layer is disposed on the magnetic layer. A metal material used in the metal oxide layer includes at least one of Ti, Ta, Ru, Hf, Al, La, and any combination thereof.
    Type: Grant
    Filed: June 6, 2013
    Date of Patent: June 16, 2015
    Assignee: International Business Machines Corporation
    Inventor: Guohan Hu
  • Patent number: 9028985
    Abstract: A magnetic recording (PMR) disk structure is described. The PMR disk structure may include a magnetic capping layer being substantially free of an oxide, an upper magnetic layer with an oxide content disposed directly below and in contact with the magnetic capping layer, and an upper exchange coupling layer disposed below the upper magnetic layer.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: May 12, 2015
    Assignee: WD Media, LLC
    Inventors: Mrugesh Desai, Kyongha Kang, Jian Zhou, B. Ramamurthy Acharya
  • Publication number: 20150124350
    Abstract: In one general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers each having a magnetic moment less than 100 emu/cc, and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers is doped with oxygen. In another general embodiment, a magnetic medium includes a recording layer having at least three exchange control layers and four magnetic layers separated from one another by the exchange control layers. An uppermost of the magnetic layers has an oxygen content of greater than 0.5 vol %. An average pitch of magnetic grains in a lowermost of the magnetic layers is 9 nm or less. A lowermost of the magnetic layers has an oxide content of at least 20 vol %.
    Type: Application
    Filed: November 1, 2013
    Publication date: May 7, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: Hoa V. Do, Sylvia H. Florez, Yoshihiro Ikeda, Kentaro Takano, Bruce D. Terris, Qing Zhu
  • Patent number: 9005781
    Abstract: A perpendicular recording medium having a perpendicular magnetic recording layer and a magnetically soft underlayer structure disposed beneath the recording layer. The soft underlayer structure includes at least first and second soft magnetic layers having different magnetic permeabilities to create a magnetic permeability gradient in the soft underlayer structure. One or more of the soft magnetic layers can be antiparallel coupled. The soft underlayer structure of the present invention having a magnetic permeability gradient advantageously leads to reduced adjacent track erasure (ATE) while maintaining good overwrite (OW) properties.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: April 14, 2015
    Assignee: Seagate Technology LLC
    Inventors: Jianing Zhou, B. Ramamurthy Acharya, E. Noel Abarra, Gunn Choe
  • Patent number: 8940418
    Abstract: A perpendicular magnetic recording (PMR) media structure with multiple exchange couple composite (ECC) layer structure is described. The PMR disk structure may include multiple soft magnetic layers with intervening hard magnetic layers and in between. The interface between the soft magnetic layers and the hard magnetic layers may be separated by exchange coupled layers.
    Type: Grant
    Filed: December 23, 2010
    Date of Patent: January 27, 2015
    Assignee: WD Media, LLC
    Inventor: Johannes van Ek
  • Patent number: 8902545
    Abstract: A magnetic recording medium may have a stacked structure including a first soft magnetic layer, an orientation control layer, a lower recording layer, an intermediate layer, and an upper recording layer that are sequentially stacked, and a second soft magnetic layer provided between the lower recording layer and the intermediate layer.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: December 2, 2014
    Assignee: Showa Denko K.K.
    Inventors: Hideaki Takahoshi, Daisuke Amiya, Hiroshi Sakai
  • Patent number: 8895164
    Abstract: A perpendicular magnetic recording medium, which includes a nonmagnetic substrate, and a first underlayer in the form of a soft magnetic under-layer (SUL), a second underlayer, an intermediate layer, a magnetic recording layer, a protective layer, and a lubricant layer sequentially laminated on the nonmagnetic substrate. The SUL has a plurality of SUL layers including a type-A SUL layer, a plurality of type-B SUL layers including at least two adjacent type-B SUL layers, and a nonmagnetic metal spacer layer disposed between the two adjacent type-B SUL layers. The type-A SUL layer may include a material selected from Co, Fe and Ni, a material selected from Cr, V and Ti, and a material selected from W, Zr, Ta and Nb. Each of the type-B SUL layers is in antiferromagnetic coupling, and may include a material selected from Co, Fe and Ni, a material selected from Cr, V and Ti, and a material selected from W, Zr, Ta and Nb.
    Type: Grant
    Filed: June 9, 2009
    Date of Patent: November 25, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Tuqiang Li, Shunji Takenoiri, Yuko Ueki
  • Patent number: 8883249
    Abstract: By improving sliding durability while ensuring a high SNR, an improvement in reliability and a further increase in recording density are to be achieved.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: November 11, 2014
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Toshiaki Tachibana, Takahiro Onoue, Keiichi Kajita
  • Patent number: 8877359
    Abstract: Provided are a magnetic disk comprising a granular magnetic recording layer which causes less noise even with a recording capacity thereof of 250 G or more bits per square inch; and a method for manufacturing the same. The magnetic disk according to the present invention comprises: a granular magnetic recording layer (20) which is formed on a disk substrate 10 directly or via an intermediate layer and which has non-magnetic regions between granular columnar particles; and an auxiliary recording layer (22) which is formed on the granular magnetic recording layer 20 and which causes exchange interaction among the granular columnar particles, wherein the auxiliary recording layer (22) contains 0.1 to 3 moles of oxygen.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: November 4, 2014
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Chiyo Saito, Tokichiro Sato, Takenori Kajiwara
  • Patent number: 8877360
    Abstract: According to one embodiment, a perpendicular magnetic recording medium includes a substrate, and a multilayered magnetic recording layer formed on the substrate by alternately stacking two or more magnetic layers and two or more nonmagnetic layers. The magnetic layers and nonmagnetic layers of the multilayered magnetic recording layer are continuous layers. The magnetic layer includes a magnetic material portion, and a plurality of pinning sites dispersed in the magnetic material portion and made of a nonmagnetic metal different from a nonmagnetic material as a main component of the nonmagnetic layer. This perpendicular magnetic recording medium has magnetic characteristics by which a gradient ? of a magnetization curve near the coercive force is 5 or more.
    Type: Grant
    Filed: November 23, 2011
    Date of Patent: November 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Soichi Oikawa
  • Patent number: 8871368
    Abstract: A perpendicular magnetic recording medium with SNR improved by reducing noise due to an auxiliary recording layer so that a higher recording density can be achieved. The perpendicular magnetic recording medium 100 includes a base, at least a magnetic recording layer 122 having a granular structure in which a non-magnetic grain boundary portion is formed between crystal particles grown in a columnar shape; a non-magnetic split layer 124 disposed on the magnetic recording layer 122 and containing Ru and oxygen; and an auxiliary recording layer 126 that is disposed on the split layer 124 and that is magnetically approximately continuous in an in-plane direction of a main surface of the base 110.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: October 28, 2014
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Takahiro Onoue, Teiichiro Umezawa, Toshiaki Tachibana, Masafumi Ishiyama
  • Patent number: 8871367
    Abstract: A perpendicular magnetic recording medium includes at least a soft-magnetic underlayer, a non-magnetic underlayer, a ferromagnetic intermediate layer, a non-magnetic intermediate layer, and a perpendicular magnetic recording layer sequentially stacked on a non-magnetic substrate. In an embodiment, the ferromagnetic intermediate layer is formed of a CoCr based alloy, a product Bs·t of a saturation magnetic flux density and film thickness of the ferromagnetic intermediate layer is within a range of 0.15 to 3.6 T·nm, and the non-magnetic intermediate layer has a film thickness of 3 nm or more.
    Type: Grant
    Filed: March 10, 2011
    Date of Patent: October 28, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Hisato Kato
  • Patent number: 8861120
    Abstract: According to one embodiment, a magnetic medium includes at least one recording layer including a first magnetic layer, a second magnetic layer and a non-magnetic layer. The first magnetic layer is form of a first magnetic material having a first magnetic anisotropy. The second magnetic layer is made of a second magnetic material having a second magnetic anisotropy different from the first magnetic anisotropy. The non-magnetic layer is made of a non-magnetic material and between the first and second magnetic layers, the first magnetic layer and the second magnetic layer being coupled such that directions of magnetization of the first and second magnetic layers are opposed to each other.
    Type: Grant
    Filed: August 10, 2012
    Date of Patent: October 14, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tao Yang, Hirofumi Suto, Tazumi Nagasawa, Kiwamu Kudo, Rie Sato, Koichi Mizushima
  • Patent number: 8841007
    Abstract: Various magnetic stack embodiments may be constructed with a soft magnetic underlayer (SUL) having a first thickness disposed between a substrate and a magnetic recording layer. A heatsink may have a second thickness and be disposed between the SUL and the magnetic recording layer. The first and second thicknesses may each be tuned to provide predetermined thermal conductivity and magnetic permeability throughout the data media.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: September 23, 2014
    Assignee: Seagate Technology LLC
    Inventors: Kai-Chieh Chang, Yinfong Ding, Ganping Ju, Timothy Klemmer, Yukiko Kubota, Thomas P. Nolan, Yingguo Peng, Jan-Ulrich Thiele, Qihong Wu, Xiaobin Zhu
  • Patent number: 8802247
    Abstract: A medium having high medium S/N and excellent corrosion resistance is achieved. In one embodiment, an adhesion layer, a soft magnetic layer, an intermediate layer, a magnetic recording layer, and a protective layer are deposited, in order, on a substrate. The soft magnetic underlayer consists at least of two soft magnetic layers, the first soft magnetic layer formed on the recording layer side being composed of an amorphous alloy containing 85 at. % or less of Co, and the second soft magnetic layer formed on the substrate side being composed of an alloy containing more than 85 at. % of Co.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: August 12, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Hiroyuki Matsumoto, Mitsuhiro Shoda, Reiko Arai, Yuzuru Hosoe, Katsumi Mabuchi
  • Patent number: 8747628
    Abstract: A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: June 10, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaoping Bian, Jack Jyh-Kau Chang, Qing Dai, Hoa V. Do, Yoshihiro Ikeda, Kentaro Takano, Chu S. Tran
  • Patent number: 8748018
    Abstract: A patterned perpendicular magnetic recording medium, such as a disk for use in hard disk drives, has a flux channeling layer (FCL) located below the recording layer (RL) in each of the discrete data islands. The disk includes a substrate, a soft underlayer (SUL) of soft magnetically permeable material on the substrate, and a nonmagnetic exchange break layer (EBL) on the SUL. A nonmagnetic separation layer (SL) is located between the FCL and the RL in the islands. The FCL has an anisotropy field substantially lower than the anisotropy field of the RL, and a magnetization equal to or higher than the magnetization of the RL. The FCL is saturated at a much lower field than the RL and thus channels the magnetic flux from the write head through the island positions. The dipolar fields from the RL above the FCL polarize the magnetization of the FCL parallel to the magnetization direction of the RL in the absence of an external field, to thereby enhance the readback signal.
    Type: Grant
    Filed: October 12, 2009
    Date of Patent: June 10, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Thomas Hauet, Olav Hellwig, Kentaro Takano
  • Patent number: 8709619
    Abstract: A low-coupling perpendicular magnetic recording media comprising a magnetic storage layer and at least one low saturation magnetization layer. The magnetic storage layer has a saturation magnetization between about 400-900 emu/cm3 and the at least one low saturation magnetization layer has a saturation magnetization below that of the magnetic storage layer.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: April 29, 2014
    Assignee: Seagate Technology LLC
    Inventors: Erol Girt, Hans Jurgen Richter, Mariana R. Munteanu, Thomas Nolan
  • Publication number: 20140093747
    Abstract: A magnetic recording medium includes a substrate and a plurality of anisotropic magnetic layers applied over the substrate. The medium further includes at least one anti-ferromagnetic coupling layer between two adjacent anisotropic magnetic layers of the plurality of anisotropic magnetic layers.
    Type: Application
    Filed: September 28, 2012
    Publication date: April 3, 2014
    Applicant: HGST NETHERLANDS B.V.
    Inventor: Ernesto E. Marinero
  • Patent number: 8673464
    Abstract: A low-coupling perpendicular magnetic recording media comprising a magnetic storage layer and at least one low saturation magnetization layer. The magnetic storage layer has a saturation magnetization between about 400-900 emu/cm3 and the at least one low saturation magnetization layer has a saturation magnetization below that of the magnetic storage layer.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: March 18, 2014
    Assignee: Seagate Technology LLC
    Inventors: Erol Girt, Hans Jurgen Richter, Mariana R. Munteanu, Thomas Nolan
  • Patent number: 8658292
    Abstract: Systems and methods for controlling the damping of magnetic media for magnetic recording are described. One such system includes a magnetic media structure for magnetic recording, the media structure including at least one base layer including an interlayer, a bottom magnetic recording layer positioned on the interlayer, and an exchange coupling layer positioned on the bottom layer; and a capping magnetic recording layer positioned on the at least one base layer, the capping recording layer including a first material configured to increase a damping constant of the capping recording layer to a first preselected level.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: February 25, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Michael L. Mallary, Gerardo A. Bertero
  • Publication number: 20140037991
    Abstract: A synthetic antiferromagnetic device includes a first tantalum layer, a reference layer disposed on the first tantalum layer and including a first cobalt iron boron layer, a second cobalt iron boron layer disposed on the first cobalt iron boron layer, a third cobalt iron boron layer and a second tantalum layer disposed between the second and third cobalt iron boron layers, a magnesium oxide spacer layer disposed on the reference layer and a cap layer disposed on the magnesium oxide spacer layer.
    Type: Application
    Filed: July 31, 2012
    Publication date: February 6, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David W. Abraham, Michael C. Gaidis
  • Patent number: 8628866
    Abstract: A magnetic recording medium that is capable of realizing both high magnetic permeability and antiferromagnetic coupling for a soft magnetic underlayer. Namely, a magnetic recording medium including at least a non-magnetic substrate on which is laminated a soft magnetic underlayer formed by antiferromagnetic coupling of a plurality of soft magnetic layers, and a perpendicular magnetic layer for which the axis of easy magnetization is oriented mainly perpendicularly to the non-magnetic substrate, wherein the soft magnetic layers contain Fe as a first main component, Co as a second main component, and also contain Ta, the soft magnetic underlayer is antiferromagnetically coupled using the second peak or a subsequently appearing peak of the antiferromagnetic coupling force, which changes according to the thickness of a spacer layer sandwiched between the plurality of soft magnetic layers, and the magnetic permeability of the soft magnetic underlayer is not less than 1,000 H/m.
    Type: Grant
    Filed: December 1, 2009
    Date of Patent: January 14, 2014
    Assignee: Showa Denko HD Singapore Pte Ltd.
    Inventors: Amarendra K Singh, Daizo Endo, Voon Siang Khoang, Xiao Chen
  • Publication number: 20140002917
    Abstract: A magnetic recording medium may have a stacked structure including a first soft magnetic layer, an orientation control layer, a lower recording layer, an intermediate layer, and an upper recording layer that are sequentially stacked, and a second soft magnetic layer provided between the lower recording layer and the intermediate layer.
    Type: Application
    Filed: June 18, 2013
    Publication date: January 2, 2014
    Applicant: SHOWA DENKO K.K.
    Inventors: Hideaki TAKAHOSHI, Daisuke Amiya, Hiroshi Sakai
  • Publication number: 20130334631
    Abstract: Memory cells are disclosed. Magnetic regions within the memory cells include an alternating structure of magnetic sub-regions and coupler sub-regions. The coupler material of the coupler sub-regions antiferromagnetically couples neighboring magnetic sub-regions and effects or encourages a vertical magnetic orientation exhibited by the neighboring magnetic sub-regions. Neighboring magnetic sub-regions, spaced from one another by a coupler sub-region, exhibit oppositely-directed magnetic orientations. The magnetic and coupler sub-regions may each be of a thickness tailored to form the magnetic region in a compact structure. Interference between magnetic dipole fields emitted from the magnetic region on switching of a free region in the memory cell may be reduced or eliminated. Also disclosed are semiconductor device structures, spin torque transfer magnetic random access memory (STT-MRAM) systems, and methods of fabrication.
    Type: Application
    Filed: June 19, 2012
    Publication date: December 19, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Wayne I. Kinney, Witold Kula, Stephen J. Kramer
  • Patent number: 8603650
    Abstract: A magnetic disk 10 for use in perpendicular magnetic recording has at least a magnetic recording layer on a substrate 1. The magnetic recording layer is composed of a ferromagnetic layer 5 of a granular structure containing silicon (Si) or an oxide of silicon (Si) between crystal grains containing cobalt (Co), a stacked layer 7 having a first layer containing cobalt (Co) or a Co alloy and a second layer containing palladium (Pd) or platinum (Pt), and a spacer layer 6 interposed between the ferromagnetic layer 5 and the stacked layer 7. After forming the ferromagnetic layer 5 on the substrate 1 by sputtering in an argon gas atmosphere, the stacked layer 7 is formed by sputtering in the argon gas atmosphere at a gas pressure lower than that used when forming the ferromagnetic layer 5.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: December 10, 2013
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventors: Yoshiaki Sonobe, Teiichiro Umezawa, Chikara Takasu
  • Patent number: 8603649
    Abstract: A perpendicular magnetic recording medium includes a magnetic recording layer 22 having a granular structure composed of crystal grains containing cobalt (Co) and grown in a columnar shape and a grain boundary portion comprising a nonmagnetic substance and formed between the crystal grains, and a continuous layer 24 of a thin film magnetically continuous in a film plane direction. The continuous layer 24 includes a plurality of layers 24a and 24b containing cobalt, chromium (Cr), and platinum (Pt). Among the layers, the layer 24a nearer to the magnetic recording layer has a greater chromium content.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: December 10, 2013
    Assignee: WD Media (Singapore) Pte. Ltd.
    Inventor: Takahiro Onoue
  • Patent number: 8582416
    Abstract: The heat-assisted magnetic recording medium of the present invention has a substrate, an under layer formed on the substrate, and a magnetic layer formed on the under layer, in which the magnetic layer includes an alloy having a L10 structure as a principle component, and the under layer is constituted by a first under layer made of an amorphous alloy or an alloy having a microcrystalline structure, a second under layer made of Cr or an alloy which contains Cr as a principle component and has a BCC structure, a third under layer made of a metal or an alloy having a BCC structure with a lattice constant of 2.98 ? or more, and a fourth under layer made of MgO.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: November 12, 2013
    Assignee: Showa Denko K.K.
    Inventors: Tetsuya Kanbe, Atsushi Hashimoto, Takayuki Fukushima