Magnetic Thin Film Patents (Class 365/171)
  • Patent number: 8593852
    Abstract: According to the embodiments, a first write enable signal that changes with a constant period and a second write enable signal that changes at a time portion in which a limit time between activation/deactivation control of word lines and activation/deactivation control of bit lines is checked are input, a plurality of core control signals in which a time interval with which the core control signals change is locally shorter than a period of the first write enable signal based on the first write enable signal and the second write enable signal that are input is generated, and an operation verification of the resistive random access memory is performed by using the generated core control signals, whereby a cycle time in an arbitrary test cycle is locally and arbitrary adjusted.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: November 26, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuaki Kawaguchi, Kazushige Kanda
  • Patent number: 8593862
    Abstract: A spin-torque transfer memory random access memory (STTMRAM) element includes a fixed layer formed on top of a substrate and a tunnel layer formed upon the fixed layer and a composite free layer formed upon the tunnel barrier layer and made of an iron platinum alloy with at least one of X or Y material, X being from a group consisting of: boron (B), phosphorous (P), carbon (C), and nitride (N) and Y being from a group consisting of: tantalum (Ta), titanium (Ti), niobium (Nb), zirconium (Zr), tungsten (W), silicon (Si), copper (Cu), silver (Ag), aluminum (Al), chromium (Cr), tin (Sn), lead (Pb), antimony (Sb), hafnium (Hf) and bismuth (Bi), molybdenum (Mo) or rhodium (Ru), the magnetization direction of each of the composite free layer and fixed layer being substantially perpendicular to the plane of the substrate.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: November 26, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Roger Klas Malmhall
  • Patent number: 8587987
    Abstract: A semiconductor memory includes a real memory cell including a selection transistor and a resistance variable element which are connected in series between a first voltage line and a second voltage line through a connection node, a real amplification transistor having a gate connected to the connection node, a source connected to a reference voltage line, and a drain connected to a real read line, and a sense amplifier to determine a logic held in the real memory cell by receiving a voltage of the real read line varied with a voltage generated in the connection node by resistance dividing between a source/drain resistance of the selection transistor, and the resistance variable element, the selection transistor receiving a read control voltage at the gate thereof.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: November 19, 2013
    Assignee: Fujitsu Limited
    Inventor: Masaki Aoki
  • Patent number: 8580408
    Abstract: An apparatus for moving a magnetic domain wall and a memory device using a magnetic field application unit are provided. The apparatus for moving a magnetic domain wall includes a magnetic layer having a plurality of magnetic domains; current supply units that are disposed on both sides of the magnetic layer and supply current to the magnetic layer; and a magnetic field application unit that is disposed on at least one surface of the magnetic layer and applies a magnetic field to the magnetic layer.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: November 12, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-su Kim, Sung-chul Lee
  • Patent number: 8582354
    Abstract: Methods and apparatus for testing a resistive memory element are provided. In an example, an initial test resistor in a resistance network coupled to a first input of a sense amplifier is selected, where the resistive memory element is coupled to a second input of the sense amplifier and an output of the sense amplifier is measured. Another test resistor is selected based on the output of the sense amplifier and both the measuring the output step and the selecting another test resistor step are repeated until the output of the sense amplifier changes. A resistance of the resistive memory element is estimated based on the last test resistor selected, where the selected test resistors and the resistive memory element pass respective currents having substantially similar amplitudes and are coupled to respective access transistors having substantially similar properties.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: November 12, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xia Li, Wah Nam Hsu, Jung Pill Kim, Taehyun Kim, Seung H. Kang
  • Patent number: 8582355
    Abstract: According to one embodiment, a magnetic memory element includes a stacked body including first and second stacked units. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. A magnetization of the first ferromagnetic layer is fixed in a direction perpendicular to the first ferromagnetic layer. A magnetization of the second ferromagnetic layer is variable. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit stacked with the first stacked unit includes third and fourth ferromagnetic layers and a second nonmagnetic layer. A magnetization of the third ferromagnetic layer is variable. The fourth ferromagnetic layer is stacked with the third ferromagnetic layer. A magnetization of the fourth ferromagnetic layer is fixed in a direction perpendicular to the fourth ferromagnetic layer. The second nonmagnetic layer is provided between the third and fourth ferromagnetic layers.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: November 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito
  • Patent number: 8576605
    Abstract: A nonvolatile semiconductor memory device according to an embodiment includes a memory cell array configured by plural memory cells each including a variable resistor and each provided between first and second lines. A control circuit applies to a memory cell through the first and second lines a writing voltage for writing data or a reading voltage for reading data. A sense amplifier circuit senses data retained in a memory cell based on a current flowing through the first line. In a data writing operation, the control circuit applies a writing voltage to each of n number of memory cells configuring one unit such that the memory cells may be supplied with different resistance values. In a data reading operation, the sense amplifier circuit compares level relationship of the resistance values of n number of memory cells configuring one unit and reads out n! patterns of data from the one unit.
    Type: Grant
    Filed: March 18, 2011
    Date of Patent: November 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takahiko Sasaki
  • Patent number: 8574730
    Abstract: Information storage devices and methods of manufacturing the same are provided. A magnetic track of the information storage device includes a magnetic layer in which at least one magnetic domain forming region and at least one magnetic domain wall forming region are alternately disposed in a lengthwise direction. The at least one magnetic domain forming regions has a different magnetic anisotropic energy relative to the at least one magnetic domain wall forming region. An intermediate layer is formed under the magnetic layer. The intermediate layer includes at least one first material region and at least one second material region. Each of the at least one first material regions and the at least one second material regions corresponds to one of the at least one magnetic domain forming regions and the at least one magnetic domain wall forming regions.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: November 5, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Young-jin Cho, Sung-chul Lee, Kwang-seok Kim, Ji-young Bae, Sun-ae Seo, Chang-won Lee
  • Patent number: 8574927
    Abstract: Using a damascene process, a cup-shaped MTJ device is formed in an opening within a dielectric layer. A passivation layer is formed on the top surfaces of the sidewalls of the cup-shaped MTJ device to enclose the top of the sidewalls, thereby reducing magnetic flux leakage. Accordingly, the MTJ device may be fabricated using the same equipment that are compatible with and commonly used in CMOS technologies/processes.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: November 5, 2013
    Assignee: Semiconductor Manufacturing International (Beijing) Corporation
    Inventors: Min-Hwa Chi, Xiufeng Han, Guoqiang Yu
  • Patent number: 8576617
    Abstract: A method of establishing a reference level includes providing first and second non-overlapping paths from a first node to a second node, providing first and second reference magnetic random access memory (MRAM) elements in the first path, providing third and fourth reference MRAM elements in the second path, measuring a first value indicative of a resistance between the first node and the second node, and setting the reference level based at least in part on the measured value. Also an associated reference circuit.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: November 5, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xiaochun Zhu, Xia Li, Wenqing Wu, Jung Pill Kim, Seung H. Kang
  • Patent number: 8576616
    Abstract: According to one embodiment, a magnetic element includes first and second conductive layers, an intermediate interconnection, and first and second stacked units. The intermediate interconnection is provided between the conductive layers. The first stacked unit is provided between the first conductive layer and the interconnection, and includes first and second ferromagnetic layer and a first nonmagnetic layer provided between the first and second ferromagnetic layers. The second stacked unit is provided between the second conductive layer and the interconnection, and includes third and fourth ferromagnetic layers and a second nonmagnetic layer provided between the third and fourth ferromagnetic layers. A magnetization direction of the second ferromagnetic layer is determined by causing a spin-polarized electron and a magnetic field to act on the second ferromagnetic layer.
    Type: Grant
    Filed: September 8, 2011
    Date of Patent: November 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito, Yuichi Ohsawa, Saori Kashiwada, Chikayoshi Kamata, Tadaomi Daibou
  • Patent number: 8575667
    Abstract: A magnetic memory device includes a free layer and a guide layer on a substrate. An insulating layer is interposed between the free layer and the guide layer. At least one conductive bridge passes through the insulating layer and electrically connects the free layer and the guide layer. A diffusion barrier may be interposed between the guide layer and the insulating layer. The device may further include a reference layer having a fixed magnetization direction on a side of the free layer opposite the insulating layer and a tunnel barrier between the reference layer and the free layer. Related fabrication methods are also described.
    Type: Grant
    Filed: May 11, 2012
    Date of Patent: November 5, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: KyungTae Nam, Jangeun Lee, Sechung Oh, Woojin Kim, Dae Kyom Kim, Junho Jeong
  • Patent number: 8576618
    Abstract: An array of rows and columns of SMT MRAM cells has each of the columns associated with one of its adjacent columns. Each of the SMT MRAM cells of the column is connected to a true data bit line and each of the SMT MRAM cells of the associated pair of columns is connected to a shared complement data bit line. A shunting switch device is connected between each of the true data bit lines and the shared complement data bit line for selectively connecting one of the true data bit lines to the shared complement data bit line to effectively reduce the resistance of the complement data bit line and to eliminate program disturb effects in adjacent non-selected columns of the SMT MRAM cells.
    Type: Grant
    Filed: May 4, 2013
    Date of Patent: November 5, 2013
    Assignees: MagIC Technologies, Inc., International Business Machines Corporation
    Inventors: Hsu-Kai Yang, Yutaka Nakamura, John Debrosse
  • Publication number: 20130286727
    Abstract: Spin Torque Transfer (STT) memory cell structures and methods are described herein. One or more STT memory cell structures comprise an annular STT stack including a nonmagnetic material between a first ferromagnetic material and a second ferromagnetic material and a soft magnetic material surrounding at least a portion of the annular STT stack.
    Type: Application
    Filed: June 25, 2013
    Publication date: October 31, 2013
    Inventors: Jun Liu, Gurtej S. Sandhu
  • Patent number: 8570792
    Abstract: A magnetoresistive random access memory (MRAM) cell includes a magnetic tunnel junction (MTJ), a top electrode disposed over the MTJ, a bottom electrode disposed below the MTJ, and an induction line disposed above or below the MTJ. The induction line is configured to induce a magnetic field at the MTJ.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: October 29, 2013
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Tien-Wei Chiang, Kai-Chun Lin, Ya-Chen Kao, Hung-Chang Yu
  • Patent number: 8570798
    Abstract: Electronic devices comprise a first substrate and a second substrate. The first substrate comprises circuitry including a plurality of conductive traces at least substantially parallel to each other through at least a portion of the first substrate. A plurality of bond pads is positioned on a surface of the first substrate and comprises a width extending over at least two of the plurality of conductive traces. A plurality of vias extends from adjacent at least some of the conductive traces to the plurality of bond pads. The second substrate is bonded to the first substrate and comprises support circuitry coupled to the plurality of bond pads on the first substrate with a plurality of conductive bumps. Memory devices and related methods of forming electronic devices and memory devices are also disclosed, as are electronic systems.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: October 29, 2013
    Assignee: Micron Technology, Inc.
    Inventors: Roy E. Meade, Gurtej S. Sandhu
  • Patent number: 8570799
    Abstract: A magnetic random access memory is configured as a read/write memory and at least a first section of the magnetic random access memory is configured to be converted to a read only memory.
    Type: Grant
    Filed: August 16, 2011
    Date of Patent: October 29, 2013
    Assignee: Intel Mobile Communications GmbH
    Inventors: Uwe Hildebrand, Josef Hausner, Matthias Obermeier, Daniel Bergmann
  • Patent number: 8570797
    Abstract: Magnetic tunnel junctions (MTJs) in magnetic random access memory (MRAM) are subject to read disturb events when the current passing through the MTJ causes a spontaneous switching of the MTJ due to spin transfer torque (STT) from a parallel state to an anti-parallel state or from an anti-parallel state to a parallel state. Because the state of the MTJ corresponds to stored data, a read disturb event may cause data loss in MRAM devices. Read disturb events may be reduced by controlling the direction of current flow through the MTJ. For example, the current direction through a reference MTJ may be selected based on the state of the reference MTJ. In another example, the current direction through a data or reference MTJ may be alternated such that the MTJ is only subject to read disturb events during approximately half the read operations on the MTJ.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: October 29, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Jung Pill Kim, Tae Hyun Kim, Kangho Lee
  • Patent number: 8570793
    Abstract: An array of rows and columns of SMT MRAM cells has each of the columns associated with one of its adjacent columns. Each of the SMT MRAM cells of the column is connected to a true data bit line and each of the SMT MRAM cells of the associated pair of columns is connected to a shared complement data bit line. A shunting switch device is connected between each of the true data bit lines and the shared complement data bit line for selectively connecting one of the true data bit lines to the shared complement data bit line to effectively reduce the resistance of the complement data bit line and to eliminate program disturb effects in adjacent non-selected columns of the SMT MRAM cells.
    Type: Grant
    Filed: May 4, 2013
    Date of Patent: October 29, 2013
    Assignees: MagIC Technologies, Inc., International Business Machines Corporation
    Inventors: Hsu-Kai Yang, Yutaka Nakamura, John Debrosse
  • Patent number: 8565010
    Abstract: A spin toque transfer magnetic random access memory (STTMRAM) element comprises a reference layer formed on a substrate, with a fixed perpendicular magnetic component. A junction layer is formed on top of the reference layer and a free layer is formed on top of the junction layer with a perpendicular magnetic orientation, at substantially its center of the free layer and switchable. A spacer layer is formed on top of the free layer and a fixed layer is formed on top of the spacer layer, the fixed layer has a fixed perpendicular magnetic component opposite to that of the reference layer. The magnetic orientation of the free layer switches relative to that of the fixed layer. The perpendicular magnetic components of the fixed layer and the reference layer substantially cancel each other and the free layer has an in-plane edge magnetization field.
    Type: Grant
    Filed: May 2, 2011
    Date of Patent: October 22, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Yuchen Zhou, Yiming Huai, Rajiv Yadav Ranjan, Jing Zhang
  • Patent number: 8565013
    Abstract: A storage element includes a storage layer that stores information on the basis of a magnetization state of a magnetic material; a fixed magnetization layer that has a magnetization serving as a reference of the information stored in the storage layer; an interlayer that is formed of a nonmagnetic material and interposed between the storage layer and the fixed magnetization layer; a cap layer that is provided to be adjacent to the storage layer and opposite to the interlayer; and a metal cap layer that is provided to be adjacent to the cap layer and opposite to the storage layer.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: October 22, 2013
    Assignee: Sony Corporation
    Inventors: Kazuhiro Bessho, Masanori Hosomi, Hiroyuki Ohmori, Yutaka Higo, Kazutaka Yamane, Tetsuya Asayama, Hiroyuki Uchida
  • Patent number: 8565014
    Abstract: An array of rows and columns of SMT MRAM cells has each of the columns associated with one of its adjacent columns. Each of the SMT MRAM cells of the column is connected to a true data bit line and each of the SMT MRAM cells of the associated pair of columns is connected to a shared complement data bit line. A shunting switch device is connected between each of the true data bit lines and the shared complement data bit line for selectively connecting one of the true data bit lines to the shared complement data bit line to effectively reduce the resistance of the complement data bit line and to eliminate program disturb effects in adjacent non-selected columns of the SMT MRAM cells.
    Type: Grant
    Filed: May 4, 2013
    Date of Patent: October 22, 2013
    Assignees: MagIC Technologies, Inc., International Business Machines Corporation
    Inventors: Hsu-Kai Yang, Yutaka Nakamura, John Debrosse
  • Patent number: 8565012
    Abstract: Magnetic memory cell comprising two conductors and a magnetic storage element between the two conductors, wherein a magnetic enhancement layer (MEL) is provided in the proximity of at least along a partial length of at least one of the two conductors. The MEL is for enhancing a magnetic field in the element when the two conductors are energized. Methods for operation and fabrication process for the memory cell are also disclosed. The memory cell is particularly for use in magnetic random access memory (MRAM) circuits, when using magnetic tunnel junction (MTJ) stacks as the magnetic storage elements.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: October 22, 2013
    Assignee: Magsil Corporation
    Inventor: Krishnakumar Mani
  • Patent number: 8565016
    Abstract: The present invention provides a method of fabricating a portion of a memory cell, the method comprising providing a first conductor in a trench which is provided in an insulating layer and flattening an upper surface of the insulating layer and the first conductor, forming a material layer over the flattened upper surface of the insulating layer and the first conductor and flattening an upper portion of the material layer while leaving intact a lower portion of the material layer over the insulating layer and the first conductor.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: October 22, 2013
    Assignee: Micron Technology, Inc.
    Inventors: Donald L. Yates, Joel A. Drewes
  • Patent number: 8559216
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a plurality of first interconnections arranged parallel, a plurality of second interconnections arranged parallel to intersect the first interconnections, and memory cell portions respectively arranged at intersecting portions between the first and second interconnections and each configured by laminating a variable-resistance element and a diode element. The diode element has a laminated structure having a first insulating film, a conductive fine grain layer and a second insulating film. The physical film thickness of the second insulating film is greater than the first insulating film and the dielectric constant of the second insulating film is greater than the first insulating film.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: October 15, 2013
    Assignee: Kabushiki Kaisha Toshbia
    Inventors: Naoki Yasuda, Daisuke Matsushita, Koichi Muraoka
  • Patent number: 8558540
    Abstract: In A method for measuring a dimensionless coupling constant of a magnetic structure includes the following steps. A step of applying an external vertical magnetic field is performed for enabling magnetic moments of a RE-TM (Rare Earth-Transition metal) alloy magnetic layer of the magnetic structure to be vertical and saturated. A step of measuring a compensation temperature is performed when the sum of the magnetization of the RE-TM alloy magnetic layer is zero. A step of applying an external parallel magnetic field to the RE-TM alloy magnetic layer is performed. A step of adjusting the temperature of the magnetic structure to the compensation temperature and measuring a hysteresis loop of the magnetic structure under the external parallel magnetic field is performed, wherein the inverse of the slope of hysteresis loop is a dimensionless coupling constant.
    Type: Grant
    Filed: October 6, 2011
    Date of Patent: October 15, 2013
    Assignee: National Yunlin University of Science and Technology
    Inventors: Te-Ho Wu, Lin-Hsiu Ye, Ying-Chuen Luo
  • Patent number: 8558333
    Abstract: A method for manipulating domain pinning and reversal in a ferromagnetic material comprises applying an external magnetic field to a uniaxial ferromagnetic material comprising a plurality of magnetic domains, where each domain has an easy axis oriented along a predetermined direction. The external magnetic field is applied transverse to the predetermined direction and at a predetermined temperature. The strength of the magnetic field is varied at the predetermined temperature, thereby isothermally regulating pinning of the domains. A magnetic storage device for controlling domain dynamics includes a magnetic hard disk comprising a uniaxial ferromagnetic material, a magnetic recording head including a first magnet, and a second magnet. The ferromagnetic material includes a plurality of magnetic domains each having an easy axis oriented along a predetermined direction.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: October 15, 2013
    Assignees: The University of Chicago, UCL Business PLC
    Inventors: Daniel M. Silevitch, Thomas F. Rosenbaum, Gabriel Aeppli
  • Patent number: 8558332
    Abstract: A method of fabricating a spin-current switched magnetic memory element includes providing a wafer having a bottom electrode, forming a plurality of layers, such that interfaces between the plurality of layers are formed in situ, in which the plurality of layers includes a plurality of magnetic layers, at least one of the plurality of magnetic layers having a perpendicular magnetic anisotropy component and including a current-switchable magnetic moment, and at least one barrier layer formed adjacent to the plurality of magnetic layers, lithographically defining a pillar structure from the plurality of layers, and forming a top electrode on the pillar structure.
    Type: Grant
    Filed: March 4, 2011
    Date of Patent: October 15, 2013
    Assignee: International Business Machines Corporation
    Inventors: Jonathan Zanhong Sun, Rolf Allenspach, Stuart Stephen Papworth Parkin, John Casimir Slonczewski, Bruce David Terris
  • Patent number: 8559219
    Abstract: A storage element includes a storage layer which has magnetization vertical to the film surface and of which the direction of magnetization changes, a magnetization fixed layer which has magnetization vertical to the film surface serving as a reference of information, and an insulating layer, and the direction of magnetization of the storage layer changes by injecting spin-polarized electrons in the laminated direction of the layer structure so as to perform information recording, the size of an effective demagnetizing field that the storage layer receives is configured to be smaller than a saturated magnetization amount of the storage layer, and a ferromagnetic layer material constituting the storage layer has CoFeB as the base material and an anti-corrosive element is added to the base material.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: October 15, 2013
    Assignee: Sony Corporation
    Inventors: Hiroyuki Uchida, Masanori Hosomi, Kazuhiro Bessho, Hiroyuki Ohmori, Yutaka Higo, Tetsuya Asayama, Kazutaka Yamane
  • Patent number: 8553449
    Abstract: A magnetic cell structure including a nonmagnetic bridge, and methods of fabricating the structure are provided. The magnetic cell structure includes a free layer, a pinned layer, and a nonmagnetic bridge electrically connecting the free layer and the pinned layer. The shape and/or configuration of the nonmagnetic bridge directs a programming current through the magnetic cell structure such that the cross sectional area of the programming current in the free layer of the structure is less than the cross section of the structure. The decrease in the cross sectional area of the programming current in the free layer enables a lower programming current to reach a critical switching current density in the free layer and switch the magnetization of the free layer, programming the magnetic cell.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: October 8, 2013
    Assignee: Micron Technology, Inc.
    Inventors: Jun Liu, Gurtej Sandhu
  • Patent number: 8553451
    Abstract: Techniques are provided for programming a spin torque transfer magnetic random access memory (STT-MRAM) cell using a unidirectional and/or symmetrical programming current. A unidirectional programming current flows through the free region of the STT-MRAM cell in one direction to switch the magnetization of the free region in at least two different directions. A symmetrical programming current switches the magnetization of the free region to either of the two different directions using a substantially similar current magnitude. In some embodiments, the STT-MRAM cell includes two fixed regions, each having fixed magnetizations in opposite directions and a free region configured to be switched in magnetization to be either parallel with or antiparallel to the magnetization of one of the fixed regions. Switching the free region to different magnetization directions may involve directing the programming current through one of the two oppositely magnetized fixed regions.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: October 8, 2013
    Assignee: Micron Technology, Inc.
    Inventor: Jun Liu
  • Patent number: 8551626
    Abstract: A magnetoresistive device having a high giant magnetoresistance (GMR) value and a moderate low resistance area product (RA) includes a first magnetic layer, a second magnetic layer, and a current confined path (CCP) spacer layer positioned between the first magnetic layer and the second magnetic layer. The spacer layer includes copper current confined paths extending between the first magnetic layer and the second magnetic layer in a matrix of magnesium oxide. The spacer layer is formed by a mixture copper and magnesium oxide, which is heattreated to form the copper current confined paths within the magnesium oxide matrix.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: October 8, 2013
    Assignee: Seagate Technology LLC
    Inventors: Qing He, Yonghua Chen, Juren Ding
  • Patent number: 8553454
    Abstract: Method and apparatus for using thermal preconditioning to write data to a non-volatile memory cell. In accordance with some embodiments, a semiconductor memory has an array of non-volatile memory cells, and a control circuit which stores a first write command from a host to write data to said array. A write circuit flows a write current through an unconditioned first selected cell having a first block address associated with the first write command to write the first selected cell to a selected data state, and concurrently passes a thermal preconditioning current through a second selected cell having a second block address associated with the first block address. The write circuit further passes a thermal preconditioning current through a third selected cell having a third block address associated with the second block address in response to receipt by the control circuit of a second write command from the host associated with the second block address.
    Type: Grant
    Filed: February 20, 2012
    Date of Patent: October 8, 2013
    Assignee: Seagate Technology LLC
    Inventors: Yiran Chen, Hai Li, Harry Hongyue Liu, Dimitar V. Dimitrov, Alan Xuguang Wang, Xiaobin Wang
  • Patent number: 8553450
    Abstract: A first magnetic layer has a magnetization fixed along one direction. A first nonmagnetic layer on the first magnetic layer functions as a first tunnel barrier. A second magnetic layer on the first nonmagnetic layer has a magnetization whose direction can be reversed by spin transfer current injection. A second nonmagnetic layer on the second magnetic layer functions as a second tunnel barrier. A third magnetic layer on the second nonmagnetic layer has a magnetization whose direction can be reversed by spin transfer through current injection at a current density different from the second magnetic layer. First magnetic, first nonmagnetic layer, and second magnetic layers exhibit a first magnetoresistive effect. Second magnetic, second nonmagnetic, and third magnetic layers exhibit a second magnetoresistive effect. A magnetoresistive effect element records and reads out data of at least three levels based on a synthetic resistance from the first and second magnetoresistive effects.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: October 8, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keiji Hosotani, Masahiko Nakayama
  • Patent number: 8547725
    Abstract: A method of programming a nonvolatile memory cell. The nonvolatile memory cell includes a diode steering element in series with a carbon storage element The method includes providing a first voltage to the nonvolatile memory cell. The first voltage reverse biases the diode steering element. The carbon storage element sets to a lower resistivity state.
    Type: Grant
    Filed: February 10, 2010
    Date of Patent: October 1, 2013
    Assignee: SanDisk 3D LLC
    Inventors: Tanmay Kumar, Roy Scheuerlein, Pankaj Kalra, Jingyan Zhang
  • Patent number: 8547736
    Abstract: A method of generating a non-reversible state at a bitcell having a first magnetic tunnel junction (MTJ) and a second MTJ includes applying a program voltage to the first MTJ of the bitcell without applying the program voltage to the second MTJ of the bitcell. A memory device includes a bitcell having a first MTJ and a second MTJ and programming circuitry configured to generate a non-reversible state at the bitcell by applying a program signal to a selected one of the first MTJ and the second MTJ of the bitcell.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: October 1, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Hari M. Rao, Jung Pill Kim, Seung H. Kang, Xiaochun Zhu, Tae Hyun Kim, Kangho Lee, Xia Li, Wah Nam Hsu, Wuyang Hao, Jungwon Suh, Nicholas K. Yu, Matthew Michael Nowak, Steven M. Millendorf, Asaf Ashkenazi
  • Patent number: 8547732
    Abstract: In one embodiment, the invention is a hybrid superconducting-magnetic memory cell and array. One embodiment of a memory cell includes a magnetoresistive element and at least one superconducting element wired in parallel with the magnetoresistive element. In a further embodiment, memory cells of the disclosed configuration are arranged to form a memory array.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: October 1, 2013
    Assignee: International Business Machines Corporation
    Inventors: John F Bulzacchelli, William J Gallagher, Mark B Ketchen
  • Patent number: 8546897
    Abstract: A magnetic memory element includes a memory layer, a reference layer, and a spin-injection layer provided between the memory layer and the reference layer. The reference layer has a structure in which at least two CoPt layers containing 20 atomic % or more and 50 atomic % or less of Pt and having a thickness of 1 nm or more and 5 nm or less are stacked with a Ru layer provided therebetween. The thickness of the Ru layer is 0.45±0.05 nm or 0.9±0.1 nm. In addition, the axis of 3-fold crystal symmetry of the CoPt layers is oriented perpendicularly to the film surface. The reference layer includes a high spin polarization layer of 1.5 nm or less containing Co or Fe as a main component at an interface with the spin-injection layer.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: October 1, 2013
    Assignee: Sony Corporation
    Inventors: Hiroyuki Ohmori, Masanori Hosomi, Kazuhiro Bessho, Yutaka Higo, Kazutaka Yamane, Hiroyuki Uchida
  • Patent number: 8547730
    Abstract: The method and system for providing a spin tunneling element are disclosed. The method and system include depositing a pinned layer, a barrier layer, and a free layer. The barrier layer has a first crystal structure and a texture. The free layer includes a first ferromagnetic layer and a second ferromagnetic layer. The first ferromagnetic is adjacent to the second ferromagnetic layer and between the second ferromagnetic layer and the barrier layer. The first ferromagnetic layer has the first crystal structure and the texture, while the second ferromagnetic layer has a second crystal structure different from the first crystal structure.
    Type: Grant
    Filed: February 24, 2010
    Date of Patent: October 1, 2013
    Assignee: Western Digital (Fremont), LLC
    Inventors: Yong Shen, Qunwen Leng
  • Patent number: 8547737
    Abstract: A magnetoresistive element according to an embodiment includes: a first ferromagnetic layer having an axis of easy magnetization in a direction perpendicular to a film plane; a second ferromagnetic layer having an axis of easy magnetization in a direction perpendicular to a film plane; a nonmagnetic layer placed between the first ferromagnetic layer and the second ferromagnetic layer; a first interfacial magnetic layer placed between the first ferromagnetic layer and the nonmagnetic layer; and a second interfacial magnetic layer placed between the second ferromagnetic layer and the nonmagnetic layer. The first interfacial magnetic layer includes a first interfacial magnetic film, a second interfacial magnetic film placed between the first interfacial magnetic film and the nonmagnetic layer and having a different composition from that of the first interfacial magnetic film, and a first nonmagnetic film placed between the first interfacial magnetic film and the second interfacial magnetic film.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: October 1, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadaomi Daibou, Eiji Kitagawa, Yutaka Hashimoto, Masaru Tokou, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Makoto Nagamine, Tadashi Kai, Hiroaki Yoda
  • Patent number: 8547733
    Abstract: A magnetic random access memory according to the present invention is provided with: a magnetic recording layer including a magnetization free region having a reversible magnetization, wherein a write current is flown through the magnetic recording layer in an in-plane direction; a magnetization fixed layer having a fixed magnetization; a non-magnetic layer provided between the magnetization free region and the magnetization fixed layer; and a heat sink structure provided to be opposed to the magnetic recording layer and having a function of receiving and radiating heat generated in the magnetic recording layer. The magnetic random access memory thus-structured radiates heat generated in the magnetic recording layer by using the heat sink structure, suppressing the temperature increase caused by the write current flown in the in-plane direction.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: October 1, 2013
    Assignee: NEC Corporation
    Inventors: Nobuyuki Ishiwata, Hideaki Numata, Norikazu Ohshima
  • Patent number: 8542525
    Abstract: A memory device comprising: a plurality of magnetoresistive random access memory (MRAM) cells arranged in rows and columns, each MRAM cell comprising a magnetic tunnel junction and a select transistor, one end of the magnetic tunnel junction being electrically coupled to the source of the select transistor; a plurality of word lines, each word line connecting MRAM cells along a row via the gate of their select transistor; a plurality of bit lines, each bit line connecting MRAM cells along a column, each bit line connecting the MRAM cells via the drain of their select transistor; wherein the memory device further comprises a plurality of source lines, each source line connecting MRAM cells along a row; and wherein each source line connecting the MRAM cells via the other end of the magnetic tunnel junction.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: September 24, 2013
    Assignee: Crocus Technology SA
    Inventors: Neal Berger, Mourad El Baraji
  • Patent number: 8542527
    Abstract: The present invention relates to a magnetic memory cell, which controls the magnetization direction of the free magnetic layer of a Magnetic Tunnel Junction (MTJ) device using a spin torque transfer, and enables the implementation of a magnetic logic circuit, in which memory and logic circuit functions are integrated. The magnetic memory cell includes an MTJ device (10) including a top electrode (11) and a bottom electrode (13), which are provided to allow current to flow therethrough, and a fixed layer (15) and a free layer (17), which are magnetic layers respectively deposited on a top and a bottom of an insulating layer (19), required to insulate the top and bottom electrodes from each other. A current control circuit (50) controls a flow of current flowing between the top and bottom electrodes, and changes a magnetization direction of the free layer according to an input logic level.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: September 24, 2013
    Assignee: EWHA University-Industry Collaboration Foundation
    Inventor: Hyungsoon Shin
  • Patent number: 8542524
    Abstract: A method of making a magnetic random access memory cell includes forming a magnetic tunnel junction (MTJ) on top of a wafer, depositing oxide on top of the MTJ, depositing a photo-resist layer on top of the oxide layer, forming a trench in the photo-resist layer and oxide layer where the trench has a width that is substantially the same as that of the MTJ. Then, the photo-resist layer is removed and a hard mask layer is deposited on top of the oxide layer in the trench and the wafer is planarized to remove the portion of the hard mask layer that is not in the trench to substantially level the top of oxide layer and the hard layer on the wafer. The remaining oxide layer is etched and the MTJ is etched to remove the portion of the MTJ which is not covered by the hard mask layer.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: September 24, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Parviz Keshtbod, Roger Klas Malmhall, Rajiv Yadav Ranjan
  • Patent number: 8542526
    Abstract: A method of making a magnetic random access memory cell includes forming a magnetic tunnel junction (MTJ) on top of a wafer, depositing oxide on top of the MTJ, depositing a photo-resist layer on top of the oxide layer, forming a trench in the photo-resist layer and oxide layer where the trench has a width that is substantially the same as that of the MTJ. Then, the photo-resist layer is removed and a hard mask layer is deposited on top of the oxide layer in the trench and the wafer is planarized to remove the portion of the hard mask layer that is not in the trench to substantially level the top of oxide layer and the hard layer on the wafer. The remaining oxide layer is etched and the MTJ is etched to remove the portion of the MTJ which is not covered by the hard mask layer.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: September 24, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Parviz Keshtbod, Roger Klas Malmhall, Rajiv Yadav Ranjan
  • Patent number: 8537604
    Abstract: A magnetoresistance element is provided with: a magnetization recording layer that is a ferromagnetic layer. The magnetization recording layer includes: a magnetization reversal region having a reversible magnetization; a first magnetization fixed region connected to a first boundary of the magnetization reversal region and having a magnetization direction fixed in a first direction; and a second magnetization fixed region connected to a second boundary of the magnetization reversal region and having a magnetization direction fixed in a second direction. At least one magnetization reversal facilitation structure which is a structure in which a magnetization is reversed more easily than the remaining portion is provided for a portion of the second magnetization fixed region.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: September 17, 2013
    Assignee: NEC Corporation
    Inventors: Tetsuhiro Suzuki, Shunsuke Fukami, Kiyokazu Nagahara, Norikazu Ohshima, Nobuyuki Ishiwata
  • Patent number: 8537622
    Abstract: A semiconductor device is disclosed. The semiconductor device includes a plurality of memory cells provided in a matrix and having a charge storage layer, a plurality of word lines provided on the charge storage layer, and an application section. When reading data from a selected memory cell selected from the plurality of memory cells, the application section applies a voltage having an opposite polarity to the voltage applied to a selected word line to non-selected word lines arranged on both adjacent sides of the selected word line.
    Type: Grant
    Filed: August 23, 2011
    Date of Patent: September 17, 2013
    Assignee: Spansion LLC
    Inventors: Fumiaki Toyama, Yukihiro Utsuno
  • Patent number: 8537607
    Abstract: A staggered magnetic tunnel junction includes a free magnetic layer extending in a lateral direction between a first end portion and an opposing second end portion and a tunneling barrier disposed between a reference magnetic layer and the first end portion and forming a magnetic tunnel junction. Current flows through the free magnetic layer in the lateral direction to switch the magnetic tunnel junction between a high resistance state and a low resistance state.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: September 17, 2013
    Assignee: Seagate Technology LLC
    Inventor: Xiaohua Lou
  • Patent number: 8537606
    Abstract: A Magnetic Random Access Memory (MRAM) includes read sensing circuitry having an equalizer device configured between a bit cell output node and a reference node of the bit cell. The equalizer is turned on to couple the output node to the reference node during an initial portion of a read operation and to decouple the output node from the reference node after an equalization delay period. A sense amplifier is enabled to provide a data output from the bit cell only after the delay period and decoupling of the output node from the reference node to provide balanced sensing speed of data represented by parallel and antiparallel state magnetic tunnel junctions (MTJs).
    Type: Grant
    Filed: February 23, 2011
    Date of Patent: September 17, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Jung Pill Kim, Tae Hyun Kim
  • Patent number: 8536668
    Abstract: A magnetic layer that includes a seed layer comprising at least tantalum and a free magnetic layer comprising at least iron. The free magnetic layer is grown on top of the seed layer and the free magnetic layer is perpendicularly magnetized. The magnetic layer may be included in a magnetic tunnel junction (MTJ) stack.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: September 17, 2013
    Assignee: International Business Machines Corporation
    Inventor: Daniel C. Worledge