Magnetic Patents (Class 365/55)
  • Patent number: 10228267
    Abstract: A magnetic sensor for the absolute counting of revolutions or linear distances includes a soft magnetic loop structure, which is populated with a predeterminable number of magnetic domains and provided with GMR or TMR layer assemblies, in which at least two separate coplanar loops having predominantly straight subsegments extending in a rhombus-like arrangement with respect to each other are provided, and the at least two loops are connected to each other via a shared intersecting point, wherein directly in front of each intersecting region in which, and after which, the domains can change from one loop to the neighboring loop, these sections of the loop structure are bent away from the conductor guidance and are curved in a siphon-like manner in this region so as to be directed into the interior of the loop structure, wherein the conductors in respective siphon-like troughs intersect each other perpendicularly.
    Type: Grant
    Filed: November 3, 2014
    Date of Patent: March 12, 2019
    Assignees: Horst Siedle GmbH & Co. KG, Leibniz-Institut fuer Photonische Technologien e.V.
    Inventors: Roland Mattheis, Marco Diegel
  • Patent number: 9146287
    Abstract: Embodiments relate to xMR sensors having very high shape anisotropy. Embodiments also relate to novel structuring processes of xMR stacks to achieve very high shape anisotropies without chemically affecting the performance relevant magnetic field sensitive layer system while also providing comparatively uniform structure widths over a wafer, down to about 100 nm in embodiments. Embodiments can also provide xMR stacks having side walls of the performance relevant free layer system that are smooth and/or of a defined lateral geometry which is important for achieving a homogeneous magnetic behavior over the wafer.
    Type: Grant
    Filed: November 15, 2010
    Date of Patent: September 29, 2015
    Assignee: Infineon Technologies AG
    Inventors: Juergen Zimmer, Klemens Pruegl, Olaf Kuehn, Andreas Strasser, Ralf-Rainer Schledz, Norbert Thyssen
  • Patent number: 8976579
    Abstract: According to one embodiment, a magnetic memory element includes: a magnetic wire, a stress application unit, and a recording/reproducing unit. The magnetic wire includes a plurality of domain walls and a plurality of magnetic domains separated by the domain walls. The magnetic wire is a closed loop. The stress application unit is configured to cause the domain walls to circle around along the closed loop a plurality of times by applying stress to the magnetic wire. The recording/reproducing unit is configured to write memory information by changing magnetizations of the circling magnetic domains as the domain walls circle around and to read the written memory information by detecting the magnetizations of the circling magnetic domains.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: March 10, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yoshiaki Fukuzumi, Hirofumi Morise, Akira Kikitsu
  • Patent number: 8934290
    Abstract: A magnetoresistance effect device including a multilayer structure having a pair of ferromagnetic layers and a barrier layer positioned between them, wherein at least one ferromagnetic layer has at least the part contacting the barrier layer made amorphous and the barrier layer is an MgO layer having a highly oriented texture structure.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: January 13, 2015
    Assignees: Canon Anelva Corporation, National Institute of Advanced Industrial Science Nad Technology
    Inventors: David D. Djayaprawira, Koji Tsunekawa, Motonobu Nagai, Hiroki Maehara, Shinji Yamagata, Naoki Watanabe, Shinji Yuasa
  • Patent number: 8908415
    Abstract: A resistive memory cell includes a switch and a resistive switching device. The switch includes a first terminal connected to a select line and a gate terminal connected to a word line. The resistive switching device is connected between a second terminal of the switch and a bit line. The resistive switching device is resettable by having a positive bias applied to the word line and a negative bias applied to the bit line.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: December 9, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chin-Chieh Yang, Wen-Ting Chu, Kuo-Chi Tu, Yu-Wen Liao, Chih-Yang Chang, Hsia-Wei Chen
  • Patent number: 8902632
    Abstract: Hybrid resistive memory devices and methods of operating and manufacturing the same, include at least two resistive memory units. At least one of the at least two resistive memory units is a resistive memory unit configured to operate in a long-term plasticity state.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: December 2, 2014
    Assignees: Samsung Electronics Co., Ltd., Gwangju Institute of Science and Technology
    Inventors: Young-bae Kim, Hyun-sang Hwang, Chang-jung Kim
  • Patent number: 8891290
    Abstract: A method and system for providing a magnetic junction residing on a substrate and usable in a magnetic device are described. The magnetic junction includes a first pinned layer, a first nonmagnetic spacer layer having a first thickness, a free layer, a second nonmagnetic spacer layer having a second thickness greater than the first thickness, and a second pinned layer. The first nonmagnetic spacer layer resides between the pinned layer and the free layer. The first pinned layer resides between the free layer and the substrate. The second nonmagnetic spacer layer is between the free layer and the second pinned layer. Further, the magnetic junction is configured such that the free layer is switchable between a plurality of stable magnetic states when a write current is passed through the magnetic junction.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: November 18, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xueti Tang, Jing Wu
  • Patent number: 8879307
    Abstract: A magnetoresistive device of an embodiment includes: first and second devices each including, a first magnetic layer having a changeable magnetization perpendicular to a film plane, a second magnetic layer having a fixed and perpendicular magnetization, and a nonmagnetic layer interposed between the first and second magnetic layers, the first and second devices being disposed in parallel on a first face of an interconnect layer; and a TMR device including a third magnetic layer having perpendicular magnetic anisotropy and having a changeable magnetization, a fourth magnetic layer having a fixed magnetization parallel to a film plane, and a tunnel barrier layer interposed between the third and fourth magnetic layers, the TMR device being disposed on a second face of the interconnect layer, and the third magnetic layer being magnetostatically coupled to the first magnetic layers of the first and second devices.
    Type: Grant
    Filed: March 20, 2012
    Date of Patent: November 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Naoharu Shimomura, Hiroaki Yoda, Junichi Ito, Minoru Amano, Chikayoshi Kamata, Keiko Abe
  • Patent number: 8869436
    Abstract: The present disclosure provides one embodiment of a method for operating a resistive random access memory (RRAM) cell. The method includes performing a forming operation to the RRAM cell with a forming voltage; performing a number of set/reset operation cycles to the RRAM cell; and performing a recreating process to the RRAM cell to recover RRAM resistance by applying a recreating voltage. Each of the number of set/reset operation cycles includes a set operation with a set voltage. The recreating voltage is greater than the set voltage.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: October 28, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chun-Yang Tsai, Yu-Wei Ting, Kuo-Ching Huang
  • Patent number: 8867254
    Abstract: This invention describes the structure and the fabrication method of a flexible memory. The flexible memory includes eight layers. The three function layers are a flexible layer of hall unit, a flexible layer of horizontal lines, and a flexible layer of vertical lines. The main fabrication process of the flexible memory includes the following: the function layers are made on the hard substrates by the traditional nano-micro methods, and then the function layers are transferred on the flexible substrates, finally the whole layers are packaged to form the flexible memory.
    Type: Grant
    Filed: July 31, 2013
    Date of Patent: October 21, 2014
    Assignee: Nanjing University
    Inventors: Yi Zhao, Yi Shi, Xiangdong Ye
  • Patent number: 8854871
    Abstract: A method for the control of the magnetic states of interacting magnetic elements comprising providing a magnetic structure with a plurality of interacting magnetic elements. The magnetic structure comprises a plurality of magnetic states based on the state of each interacting magnetic element. The desired magnetic state of the magnetic structure is determined. The active resonance frequency and amplitude curve of the desired magnetic state is determined. Each magnetic element of the magnetic structure is then subjected to an alternating magnetic field or electrical current having a frequency and amplitude below the active resonance frequency and amplitude curve of said desired magnetic state and above the active resonance frequency and amplitude curve of the current state of the magnetic structure until the magnetic state of the magnetic structure is at the desired magnetic state.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: October 7, 2014
    Assignee: U.S. Department of Energy
    Inventors: Shikha Jain, Valentyn Novosad
  • Patent number: 8811062
    Abstract: A variable resistance memory device has memory cells that are operated by Joule's heat and which are highly thermally efficient. Conductive patterns are formed on a substrate; sacrificial patterns exposing a portion of the top surface of each of the conductive patterns are formed on the conductive patterns, lower electrodes are formed by etching upper portions of the conductive patterns using the sacrificial patterns as an etching mask, then mold patterns are formed on the lower electrodes and cover exposed sidewall surfaces of the sacrificial patterns, and then the sacrificial patterns are replaced with variable resistance patterns.
    Type: Grant
    Filed: June 17, 2013
    Date of Patent: August 19, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Byeung Chul Kim
  • Patent number: 8760913
    Abstract: A magnetic detecting element includes a laminated structure where a fixed magnetic layer and a free magnetic layer are laminated through a non-magnetic material layer, wherein the fixed magnetic layer is a self-pinned type where a first magnetic layer and a second magnetic layer are laminated through a non-magnetic intermediate layer and the first magnetic layer and the second magnetic layer are antiparallelly magnetization-fixed, and the second magnetic layer is in contact with the non-magnetic material layer. The first magnetic layer is formed using FeCo serving as a material having a higher coercive force than the second magnetic layer. The film thickness of the first magnetic layer falls within a range greater than or equal to 10 ? and less than or equal to 17 ?, and is thinner than the film thickness of the second magnetic layer. The non-magnetic intermediate layer is formed using Rh.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: June 24, 2014
    Assignee: Alps Electric Co., Ltd.
    Inventors: Fumihito Koike, Kota Asatsuma
  • Patent number: 8755220
    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: July 16, 2013
    Date of Patent: June 17, 2014
    Assignee: International Business Machines Corporation
    Inventors: John F. Bulzacchelli, William J. Gallagher, Mark B. Ketchen
  • Patent number: 8659938
    Abstract: A magnetic random access memory (MRAM) cell including a magnetic tunnel junction including a tunnel barrier layer between a first magnetic layer having a first magnetization direction, and a second magnetic layer having a second adjustable magnetization to vary a junction resistance of the magnetic tunnel junction from a first to a second junction resistance level; said magnetic tunnel junction further including a switching resistant element electrically connected to the magnetic tunnel junction and having a switching resistance switchable from a first to a second switching resistance level when a switching current is passed through the switching resistant element, such that a resistance of the MRAM cell can have at least four different cell resistance levels depending of the resistance level of the junction resistance and the switching resistance. The disclosed MRAM cell achieves improved read margin and allows for writing at least four different cell resistance levels.
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: February 25, 2014
    Assignee: Crocus Technology SA
    Inventor: Ioan Lucian Prejbeanu
  • Patent number: 8654576
    Abstract: Provided is a spin valve element capable of performing multi-value recording, which includes a pair of ferromagnetic layers having different coercivities from each other, and sandwiching an insulating layer or a non-magnetic layer. The ferromagnetic layer having the smaller coercivity has a substantially circular in-plane profile, and a plurality of island-shaped non-magnetic portions IN, IE, IW, and IS are included. In addition, a storage device is manufactured by using such a spin valve element.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: February 18, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Haruo Kawakami, Yasushi Ogimoto
  • Patent number: 8637170
    Abstract: A magnetic sensor comprises a support; a nonmagnetic conductive layer disposed on the support; a fixed magnetization layer disposed on a first part of the nonmagnetic conductive layer and on the support; a free magnetization layer disposed on a second part of the nonmagnetic conductive layer different from the first part and on the support; and a nonmagnetic low resistance layer, disposed on a part overlapping the nonmagnetic conductive layer in at least one of the fixed magnetization layer and free magnetization layer, having an electrical resistivity lower than that of the one layer.
    Type: Grant
    Filed: May 26, 2009
    Date of Patent: January 28, 2014
    Assignee: TDK Corporation
    Inventor: Tomoyuki Sasaki
  • Patent number: 8638597
    Abstract: A memory array includes a plurality of magneto-resistive changing memory cells. Each resistive changing memory cell is electrically between a source line and a bit line and a transistor electrically between the resistive changing memory cell and the bit line. The transistor has a gate electrically between a source region and a drain region and the source region being electrically between the r magneto-resistive changing memory cell and the gate. A word line is electrically coupled to the gate. A bit line charge accumulation sensing for magneto-resistive changing memory is also disclosed.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: January 28, 2014
    Assignee: Seagate Technology LLC
    Inventors: Chulmin Jung, Yong Lu, Kang Yong Kim, Young Pil Kim
  • Patent number: 8619450
    Abstract: A method of adjusting a resistive change element using a reference is disclosed. The method comprises inspecting a resistive change element to determine a first state; comparing the first state to a reference wherein said reference provides stimulus parameters corresponding to a transition from the first state to a second state; and applying the stimulus parameters to the resistive change element. A resistive change memory cell array is also disclosed.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: December 31, 2013
    Assignee: Nantero Inc.
    Inventor: Darlene Hamilton
  • 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: 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: 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: 8503218
    Abstract: A nonvolatile memory device includes: a memory array including a plurality of memory banks which are arranged in a first direction; a write global bit line and a read global bit line extending in the first direction to be shared by the memory banks; a write circuit connected to the write global bit line and disposed on a first side of the memory array; and a read circuit connected to the read global bit line and disposed on a second side of the memory array opposite the first side of the memory array, wherein each of the memory banks extends in a second direction different from the first direction and comprises a plurality of nonvolatile memory cells, each of the nonvolatile memory cells having a variable resistive element whose resistance value varies according to data stored therein.
    Type: Grant
    Filed: June 8, 2011
    Date of Patent: August 6, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-Young Kim, Ki-Whan Song
  • Patent number: 8456903
    Abstract: A magnetic element having a ferromagnetic pinned layer, a ferromagnetic free layer, a non-magnetic spacer layer therebetween, and a porous non-electrically conducting current confinement layer between the free layer and the pinned layer. The current confinement layer forms an interface either between the free layer and the non-magnetic spacer layer or the pinned layer and the non-magnetic spacer layer.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: June 4, 2013
    Assignee: Seagate Technology LLC
    Inventors: Michael Xuefei Tang, Ming Sun, Dimitar V. Dimitrov, Patrick Ryan
  • Patent number: 8456888
    Abstract: A semiconductor memory device with a variable resistance element includes a plurality of active areas isolated from one another by an isolation layer formed in a substrate, a plurality of word lines crossing over the plurality of active areas, an auxiliary source line disposed between two selected word lines and commonly connected to at least two active areas among the plurality of active areas between the two selected word lines, and a plurality of contact plugs each connected to a corresponding active area.
    Type: Grant
    Filed: October 7, 2010
    Date of Patent: June 4, 2013
    Assignee: Hynix Semiconductor Inc.
    Inventor: Seung Hyun Lee
  • Patent number: 8456882
    Abstract: A method and system for providing a magnetic junction usable in a magnetic memory are described. The magnetic junction includes first and second pinned layers, first and second nonmagnetic spacer layers, and a free layer. The first pinned layer has a first pinned layer magnetic moment and is nonmagnetic layer-free. The first nonmagnetic spacer layer resides between the first pinned and free layers. The free layer resides between the first and second nonmagnetic spacer layers. The second pinned layer has a second pinned layer magnetic moment and is nonmagnetic layer-free. The second nonmagnetic spacer layer resides between the free and second pinned layers. The first and second pinned layer magnetic moments are antiferromagnetically coupled and self-pinned. The magnetic junction is configured to allow the free layer to be switched between stable magnetic states when a write current is passed through the magnetic junction.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: June 4, 2013
    Assignee: Grandis, Inc.
    Inventors: Dmytro Apalkov, Vladimir Nikitin, David Druist, Steven M. Watts
  • Patent number: 8395935
    Abstract: A programmable memory array is disclosed in which the phase change memory cells are self-aligned at the access devices and at the cross-points of the bit lines and the word lines. A method for making the array employs one line mask to define the bit lines and another line mask to define the word lines. The front end of line (FEOL) memory cell elements are in the same layer as the polysilicon gates. The bit lines and the word lines intersect over the devices, and the memory cell elements are formed at the intersections of the bit lines and the word line.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: March 12, 2013
    Assignee: Macronix International Co., Ltd.
    Inventors: Hsiang-Lan Lung, Erh-Kun Lai
  • Patent number: 8363448
    Abstract: According to one embodiment, a semiconductor memory device includes a memory cell, a power supply circuit, an interconnection and a discharging circuit. The memory cell includes a variable resistance element whose resistance varies by application of a voltage. The power supply circuit outputs the voltage to be applied to the memory cell. The interconnection is formed between the power supply circuit and the memory cell and supplies the voltage output from the power supply circuit to the memory cell. The discharging circuit is connected to the interconnection. The discharging circuit discharges electric charge accumulated in the interconnection after a first operation of applying the voltage to the memory cell is ended and before a second operation of applying the voltage to the memory cell next is started.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: January 29, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takafumi Shimotori
  • Patent number: 8355274
    Abstract: A current steering element which can prevent occurrence of write disturb even when electric pulses having different polarities are applied and can cause large current to flow through a variable resistance element, and with which data can be written without problem. In a storage element (3) including: a variable resistance element (1) whose electric resistance value changes in response to application of electric pulses having a positive polarity and a negative polarity and which maintains the changed electric resistance value; and the current steering element (2) that steers current flowing through the variable resistance element (1) when the electric pulses are applied, the current steering element (2) includes: a first electrode (32); a second electrode (31); and a current steering layer (33) interposed between the first electrode (32) and the second electrode (31). When the current steering layer (33) includes SiNx (0<x?0.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: January 15, 2013
    Assignee: Panasonic Corporation
    Inventors: Koji Arita, Takumi Mikawa, Mitsuteru IIjima, Kenji Tominaga
  • Patent number: 8350347
    Abstract: The invention relates to a writable magnetic element comprising a stack of layers presenting a write magnetic layer, wherein the stack has a central layer of at least one magnetic material presenting a direction of magnetization that is perpendicular to the plane of the central layer, said central layer being sandwiched between first and second outer layers of non-magnetic materials, the first outer layer comprising a first non-magnetic material and the second outer layer comprising a second non-magnetic material that is different from the first non-magnetic material, at least the second non-magnetic material being electrically conductive, and wherein it includes a device for causing current to flow through the second outer layer in a current flow direction parallel to the plane of the central layer, and a device for applying a magnetic field along a magnetic field direction that is perpendicular to the plane of the central layer.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: January 8, 2013
    Assignees: Centre National de la Recherche Scientifique, Commissariat a l'Energie Atomique et aux Energies Alternatives, Universite Joseph Fourier, Institut Catala de Nanotechnologia, Institucio Catalana de Recerca I Estudis Avancats (ICREA)
    Inventors: Gilles Gaudin, Ioan Mihai Miron, Pietro Gambardella, Alain Schuhl
  • Patent number: 8310864
    Abstract: A memory device is described that comprises a plurality of bit lines and an array of vertical transistors arranged on the plurality of bit lines. A plurality of word lines is formed along rows of vertical transistors in the array which comprise thin film sidewalls of word line material and arranged so that the thin film sidewalls merge in the row direction, and do not merge in the column direction, to form word lines. The word lines provide “surrounding gate” structures for embodiments in which the vertical transistors are field effect transistors. Memory elements are formed in electrical communication with the vertical transistors. A fully self-aligned process is provided in which the word lines and memory elements are aligned with the vertical transistors without additional patterning steps.
    Type: Grant
    Filed: June 15, 2010
    Date of Patent: November 13, 2012
    Assignees: Macronix International Co., Ltd., International Business Machines Corporation
    Inventors: Hsiang-Lan Lung, Chung H Lam, Erh-Kun Lai, Matthew J. Breitwisch
  • Patent number: 8309166
    Abstract: A magnetic cell structure including a nonmagnetic filament contact, and methods of fabricating the structure are provided. The magnetic cell structure includes a free layer, a pinned layer, an insulative layer between the free and pinned layers, and a nonmagnetic filament contact in the insulative layer which electrically connects the free and pinned layers. The nonmagnetic filament contact is formed from a nonmagnetic source layer, also between the free and pinned layers. The filament contact directs a programming current through the magnetic cell structure such that the cross sectional area of the programming current in the free layer 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: June 6, 2011
    Date of Patent: November 13, 2012
    Assignee: Micron Technology, Inc.
    Inventors: Jun Liu, Gurtej Sandhu
  • Patent number: 8310865
    Abstract: A semiconductor memory device comprises a memory cell, first and second voltage generating circuits generating first and second voltages, and a control circuit. A memory element and a diode included in the memory cell are connected in series between first and second lines. The first voltage has no temperature dependence, and the second voltage has a temperature dependence opposite to that of a forward voltage of the diode. The control circuit detects a resistance state of the memory element in accordance with a change in current flowing in the memory cell in a state where the first/second voltage is applied to the first/second in a read operation of the memory cell.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: November 13, 2012
    Assignee: Elpida Memory Inc.
    Inventor: Shuichi Tsukada
  • Patent number: 8261367
    Abstract: Data, stored in MRAM-cells should be protected against misuse or read-out by unauthorized persons. The present invention provides an array of MRAM-cells provided with a security device for destroying data stored in the MRAM-cells when they are tampered with. This is achieved by placing a permanent magnet adjacent the MRAM-array in combination with a soft-magnetic flux-closing layer. As long as the soft-magnetic layer is present, the magnetic field lines from the permanent magnet are deviated and flow through this soft-magnetic layer. When somebody is tampering with the MRAM-array, e.g. by means of reverse engineering, and the flux-closing layer is removed, the flux is no longer deviated and affects the nearby MRAM-array, thus destroying the data stored in the MRAM-cells.
    Type: Grant
    Filed: February 19, 2010
    Date of Patent: September 4, 2012
    Assignee: Crocus Technology, Inc.
    Inventors: Kars-Michiel Hubert Lenssen, Robert Jochemsen
  • Patent number: 8248846
    Abstract: To provide a magnetic memory device that can suppress the reduction of function of a magnetic memory element, and a manufacturing method thereof. A magnetic memory device includes a magnetic memory element capable of holding data based on a magnetized state thereof, and a digit line and a bit line which are capable of changing the magnetized state of the magnetic memory element by a magnetic field generated. The magnetic memory element is disposed above the digit line and the bit line at an intersection part of the digit line and the bit line. The digit line has a first width at the intersection part, and the bit line has a second width at the intersection part. The first width is larger than a third width of the magnetic memory element, and the second width is smaller than a fourth width of the magnetic memory element.
    Type: Grant
    Filed: March 22, 2010
    Date of Patent: August 21, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Motoi Ashida
  • Patent number: 8203869
    Abstract: A memory array includes a plurality of magneto-resistive changing memory cells. Each resistive changing memory cell is electrically between a source line and a bit line and a transistor electrically between the resistive changing memory cell and the bit line. The transistor has a gate electrically between a source region and a drain region and the source region being electrically between the magneto-resistive changing memory cell and the gate. A word line is electrically coupled to the gate. A bit line charge accumulation sensing for magneto-resistive changing memory is also disclosed.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: June 19, 2012
    Assignee: Seagate Technology LLC
    Inventors: Chulmin Jung, Yong Lu, Kang Yong Kim, Young Pil Kim
  • Patent number: 8174879
    Abstract: A biosensor and a sensing cell array using a biosensor are disclosed. Adjacent materials containing a plurality of different ingredients are analyzed to determine the ingredients based on their magnetic susceptibility or dielectric constant. A sensing cell array includes such as a magnetization pair detection sensor including a MTJ (Magnetic Tunnel Junction) or GMR (Giant Magnetoresistive) device, a magnetoresistive sensor including a MTJ device and a magnetic material (current line), a dielectric constant sensor including a sensing capacitor and a switching device, a magnetization hole detection sensor including a MTJ or GMR device, a current line, a free ferromagnetic layer and a switching device, and a giant magnetoresistive sensor including a GMR device, a switching device and a magnetic material (or forcing wordline).
    Type: Grant
    Filed: October 26, 2009
    Date of Patent: May 8, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventors: Hee Bok Kang, Dong Yun Jeong, Jae Hyoung Lim, Young Jin Park, Kye Nam Lee, In Woo Jang, Seaung Suk Lee, Chang Shuk Kim
  • Patent number: 8154905
    Abstract: A semiconductor memory according to an aspect of the invention including first and second bit lines, a word line, a resistive memory element which has one end and the other end, the one end being connected with the first bit line, a selective switch element which has a current path and a control terminal, one end of the current path being connected with the other end of the resistive memory element, the other end of the current path being connected with the second bit line, the control terminal being connected with the word line, a first column switch connected with the first bit line, a second column switch connected with the second bit line, wherein the first and second bit lines is activated and then the word line is activated when starting writing or reading data with respect to the resistive memory element.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tsuneo Inaba
  • Patent number: 8111541
    Abstract: A method and structure of a bistable resistance random access memory comprise a plurality of programmable resistance random access memory cells where each programmable resistance random access memory cell includes multiple memory members for performing multiple bits for each memory cell. The bistable RRAM includes a first resistance random access member connected to a second resistance random access member through interconnect metal liners and metal oxide strips. The first resistance random access member has a first resistance value Ra, which is determined from the thickness of the first resistance random access member based on the deposition of the first resistance random access member. The second resistance random access member has a second resistance value Rb, which is determined from the thickness of the second resistance random access member based on the deposition of the second resistance random access member.
    Type: Grant
    Filed: March 2, 2010
    Date of Patent: February 7, 2012
    Assignee: Macronix International Co., Ltd.
    Inventors: Erh-Kun Lai, ChiaHua Ho, Kuang Yeu Hsieh
  • Patent number: 8098538
    Abstract: Method and apparatus for using a uni-directional write current to store different logic states in a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, the memory cell has an unpinned ferromagnetic reference layer adjacent a cladded conductor, a ferromagnetic storage layer and a tunneling barrier between the reference layer and the storage layer. Passage of a current along the cladded conductor induces a selected magnetic orientation in the reference layer, which is transferred through the tunneling barrier for storage by the storage layer. Further, the orientation of the applying step is provided by a cladding layer adjacent a conductor along which a current is passed and the current induces a magnetic field in the cladding layer of the selected magnetic orientation.
    Type: Grant
    Filed: May 4, 2011
    Date of Patent: January 17, 2012
    Assignee: Seagate Technology LLC
    Inventors: Daniel Seymour Reed, Yong Lu, Song S. Xue, Dimitar V. Dimitrov, Paul E. Anderson
  • Patent number: 8077497
    Abstract: A resistive memory device includes: a storage element; a first line and a second line; a first drive controller; and a second drive controller.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: December 13, 2011
    Assignee: Sony Corporation
    Inventor: Kentaro Ogata
  • Publication number: 20110286255
    Abstract: A magnetic circuit in one aspect comprises a plurality of tapered magnetic wires each having a relatively wide input end and a relatively narrow output end, with the output end of a first one of the tapered magnetic wires being coupled to the input end of a second one of the tapered magnetic wires. Each of the tapered magnetic wires is configured to propagate a magnetic domain wall along a length of the wire in a direction of decreasing width from its input end to its output end. In an illustrative embodiment, the magnetic circuit comprises a logic buffer that includes at least one heating element. The heating element may be controlled to facilitate transfer of a magnetic moment from the output end of the first tapered magnetic wire to the input end of the second tapered magnetic wire.
    Type: Application
    Filed: May 19, 2010
    Publication date: November 24, 2011
    Applicant: International Business Machines Corporation
    Inventors: Daniel Christopher Worledge, David William Abraham
  • Patent number: 8040724
    Abstract: A magnetic random access memory includes: a magnetic recording layer including a ferromagnetic layer and having perpendicular magnetic anisotropy; and a magnetic reading layer provided on the magnetic recording layer and used for reading information. The magnetic recording layer includes: a magnetization switching area having reversible magnetization; a first magnetization pinned area connected to a first boundary of the magnetization switching area and having magnetization whose direction is pinned in a first direction; and a second magnetization pinned area connected to a second boundary of the magnetization switching area and having magnetization whose direction is pinned in a second direction. The magnetic reading layer includes: a magnetic sensing layer whose direction of magnetization changes based on a direction of the magnetization of the magnetization switching area; a nonmagnetic barrier layer provided on the magnetic sensing layer; and a pinned layer provided on the nonmagnetic barrier layer.
    Type: Grant
    Filed: July 7, 2008
    Date of Patent: October 18, 2011
    Assignee: NEC Corporation
    Inventors: Tetsuhiro Suzuki, Norikazu Ohshima, Shunsuke Fukami, Kiyokazu Nagahara, Nobuyuki Ishiwata
  • Patent number: 7972752
    Abstract: A resist pattern forming method capable of obtaining a smooth resist pattern. An exemplary method may utilize a photomask including a plurality of mask cells arranged in the form of a matrix. The length of one side of each of the mask cells may be smaller than the length corresponding to the resolution limit of the optical system of the exposure device. Each mask cell may have one or both of a light transmission region and a light shielding region, and the intensity of light passing through each mask cell may be determined by the ratio of the area of the light transmission region to the area of the mask cell. The photomask may be positioned at a vertical focus position other than the optimal focus position. The resist film may be exposed with light and may then be developed to produce the resist pattern.
    Type: Grant
    Filed: June 6, 2008
    Date of Patent: July 5, 2011
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Takamitsu Furukawa
  • Patent number: 7969768
    Abstract: A magnetic random access memory of an aspect of the present invention including a magnetoresistive effect element having a fixed layer whose magnetization direction is fixed, a recording layer whose magnetization direction is reversible, and a non-magnetic layer provided between the fixed and recording layers, wherein the magnetization directions of the fixed and recording layers are in a parallel state or in an anti-parallel state depending on a direction of a current flowing between the fixed and recording layers, a first transistor having a gate and a first current path having one end connected to the fixed layer, a second transistor having a gate and a second current path having one end connected to the recording layer, a first bit line to which other end of the first current path is connected, and a second bit line to which other end of the second current path is connected.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: June 28, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryousuke Takizawa, Kenji Tsuchida
  • Patent number: 7965544
    Abstract: An inadvertent write can be prevented when a read is performed. The duration of the write current pulse for writing information in the magnetic memory layer is longer than the duration of the read current pulse for reading the information from the magnetic memory layer.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: June 21, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Masatoshi Yoshikawa, Tatsuya Kishi, Hiroaki Yoda
  • Patent number: 7940592
    Abstract: Method and apparatus for using a uni-directional write current to store different logic states in a non-volatile memory cell, such as a modified STRAM cell. In some embodiments, the memory cell has an unpinned ferromagnetic reference layer adjacent a cladded conductor, a ferromagnetic storage layer and a tunneling barrier between the reference layer and the storage layer. Passage of a current along the cladded conductor induces a selected magnetic orientation in the reference layer, which is transferred through the tunneling barrier for storage by the storage layer. Further, the orientation of the applying step is provided by a cladding layer adjacent a conductor along which a current is passed and the current induces a magnetic field in the cladding layer of the selected magnetic orientation.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: May 10, 2011
    Assignee: Seagate Technology LLC
    Inventors: Daniel Seymour Reed, Yon Lu, Song S. Xue, Dimitar V. Dimitrov, Paul E. Anderson
  • Patent number: 7936595
    Abstract: Each layer in the magnetic multilayer film is a closed ring or oval ring and the magnetic moment or flux of the ferromagnetic film in the magnetic unit is in close state either clockwise or counterclockwise. A metal core is put in the geometry center position in the close-shaped magnetic multilayer film. The cross section of the metal core is a corresponding circular or oval. A MRAM is made of the closed magnetic multilayer film with or without a metal core. The close-shaped magnetic multilayer film is formed by micro process method. The close-shaped magnetic multilayer film can be used broadly in a great variety of device that uses a magnetic multilayer film as the core, such as MRAM, magnetic bead in computer, magnetic sensitive sensor, magnetic logic device and spin transistor.
    Type: Grant
    Filed: December 31, 2006
    Date of Patent: May 3, 2011
    Assignee: Institute of Physics, Chinese Academy of Sciences
    Inventors: Xiufeng Han, Ming Ma, Qihang Qin, Hongxiang Wei, Lixian Jiang, Yunan Han
  • Patent number: 7864564
    Abstract: Between the value of an electric current and the supply duration for which the electric current is supplied that cause magnetization reversal, there is the relation of monotonous decrease. This means that, as the supply duration is shortened, the threshold current value for causing the magnetization reversal is larger. Therefore, in terms of suppressing occurrence of read disturb, the read current supply duration may be shortened to increase the threshold value of the current causing the magnetization reversal and thereby ensure a sufficient read disturb margin. Therefore, the read current supply duration may be shortened relative to the write current supply duration ensure the read disturb margin and suppress occurrence of read disturb.
    Type: Grant
    Filed: December 14, 2009
    Date of Patent: January 4, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Hideto Hidaka
  • Patent number: 7826258
    Abstract: A magnetic memory or MRAM memory system comprising an M×N crossbar array of MRAM cells. Each memory cell stores binary data bits with switchable magnetoresistive tunnel junctions (MJT) where the electrical conductance changes as the magnetic moment of one electrode (the storage layer) in the MJT switches direction. The switching of the magnetic moment is assisted by a phase transition interlayer that transitions from antiferromagnetic to ferromagnetic at a well defined, above ambient temperature.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: November 2, 2010
    Assignee: Carnegie Mellon University
    Inventors: Jian-Gang Zhu, Yi Luo, Xin Li