Including Magnetic Element Patents (Class 365/225.5)
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Patent number: 11901002Abstract: System and method to localize a position of an RRAM filament of resistive memory device at very low bias voltages using a scanning laser beam. The approach is non-invasive and allows measurement of a large number of devices for creating statistics relating to the filament formation. A laser microscope system is configured to perform a biasing the RRAM cell with voltage (or current). Concurrent to the applied bias, a laser beam is generated and aimed at different positions of the RRAM cell (e.g., by a raster scanning). Changes in the current (or voltage) flowing through the cell are measured. The method creates a map of the current (or voltage) changes at the different laser positions and detects a spot in the map corresponding to higher (or lower) current (or voltage). The method determines the (x,y) position of the spot compared to the edge/center of the RRAM cell.Type: GrantFiled: December 1, 2021Date of Patent: February 13, 2024Assignee: International Business Machines CorporationInventors: Franco Stellari, Ernest Y. Wu, Takashi Ando, Peilin Song
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Patent number: 11366024Abstract: A technique for measuring the resistance of a resistive element 4 in the presence of a series diode is provided. By supplying three different currents I1, I2, I3 and measuring corresponding voltages V1, V2, V3 across the resistive element and diode, the voltages can be combined to at least partially eliminate an error in the measured resistance of the resistive element caused by a voltage drop across the diode. A technique for current control in an array of resistive elements is also described in which a column of resistive elements is provided with two or more current sources switched so that while one current source is providing current to the column line corresponding to a selected resistive element, another current source has its amount of current adjusted.Type: GrantFiled: October 4, 2017Date of Patent: June 21, 2022Assignee: EVONETIX LTDInventors: Matthew James Hayes, Vasile Dan Juncu
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Patent number: 10734051Abstract: Embodiments provide a magnetic memory device and a method of writing a magnetic memory device. The magnetic memory device includes a magnetic tunnel junction including a reference layer, a free layer and a tunnel barrier layer between the reference and free layers, and a first conductive line adjacent to the free layer. A first spin-orbit current having a frequency decreasing with time flows through the first conductive line. The writing method includes applying the first spin-orbit current having the frequency decreasing with time to the first conductive line.Type: GrantFiled: October 3, 2019Date of Patent: August 4, 2020Assignee: Samsung Electronics Co., Ltd.Inventors: Woo Chang Lim, Kyung-Jin Lee, Gyungchoon Go, Seung-Jae Lee
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Patent number: 10482939Abstract: Embodiments provide a magnetic memory device and a method of writing a magnetic memory device. The magnetic memory device includes a magnetic tunnel junction including a reference layer, a free layer and a tunnel barrier layer between the reference and free layers, and a first conductive line adjacent to the free layer. A first spin-orbit current having a frequency decreasing with time flows through the first conductive line. The writing method includes applying the first spin-orbit current having the frequency decreasing with time to the first conductive line.Type: GrantFiled: November 27, 2017Date of Patent: November 19, 2019Assignees: SAMSUNG ELECTRONICS CO., LTD., KOREA UNIVERSITY Research and Business FoundationInventors: Woo Chang Lim, Kyung-Jin Lee, Gyungchoon Go, Seung-Jae Lee
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Patent number: 9865322Abstract: Described is an apparatus for improving read and write margins. The apparatus comprises: a sourceline; a first bitline; a column of resistive memory cells, each resistive memory cell of the column coupled at one end to the sourceline and coupled to the first bitline at another end; and a second bitline in parallel to the first bitline, the second bitline to decouple read and write operations on the bitline for the resistive memory cell. Described is also an apparatus which comprises: a sourceline; a bitline; a column of resistive memory cells, each resistive memory cell in the column coupled at one end to the sourceline and coupled to the bitline at another end; and sourceline write drivers coupled to the bitline and the sourceline, wherein the sourceline write drivers are distributed along the column of resistive memory cells.Type: GrantFiled: September 29, 2016Date of Patent: January 9, 2018Assignee: INTEL CORPORATIONInventors: Cyrille Dray, Blake C. Lin, Fatih Hamzaoglu, Liqiong Wei, Yih Wang
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Patent number: 9520192Abstract: In a memory device where writing a memory cell to a first bit state takes longer than writing to the second bit state, selectively executing the write operation can amortize the performance cost of writing the bit state that takes longer to write. Write logic dequeues multiple cachelines from a write buffer and sets all bits of all cachelines to the first bit state in a single write operation. The write logic then executes separate write operations on each cacheline separately to selectively write memory cells of each respective cacheline to the second bit state.Type: GrantFiled: June 30, 2014Date of Patent: December 13, 2016Assignee: INTEL CORPORATIONInventors: Helia Naeimi, Shih-Lien L Lu, Charles Augustine
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Patent number: 9478273Abstract: Described is an apparatus for improving read and write margins. The apparatus comprises: a sourceline; a first bitline; a column of resistive memory cells, each resistive memory cell of the column coupled at one end to the sourceline and coupled to the first bitline at another end; and a second bitline in parallel to the first bitline, the second bitline to decouple read and write operations on the bitline for the resistive memory cell. Described is also an apparatus which comprises: a sourceline; a bitline; a column of resistive memory cells, each resistive memory cell in the column coupled at one end to the sourceline and coupled to the bitline at another end; and sourceline write drivers coupled to the bitline and the sourceline, wherein the sourceline write drivers are distributed along the column of resistive memory cells.Type: GrantFiled: October 31, 2013Date of Patent: October 25, 2016Assignee: Intel CorporationInventors: Cyrille Dray, Blake C. Lin, Fatih Hamzaoglu, Liqiong Wei, Yih Wang
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Patent number: 9318180Abstract: In one embodiment of the invention, there is provided a magnetic random access (MRAM) device. The device comprises a plurality of MRAM cells, wherein each MRAM cell comprises a magnetic bit, and write conductors defined by conductors patterned in a second metal layer above the magnetic bit; and a gate formed below the magnetic bit between a source and a drain; and addressing circuits to address the MRAM cells.Type: GrantFiled: May 20, 2014Date of Patent: April 19, 2016Assignee: III HOLDINGS 1, LLCInventor: Krishnakumar Mani
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Patent number: 9305624Abstract: A memory device includes a substrate, and, disposed thereover, an array of vertical memory switches. Each switch has at least three terminals and a cross-sectional area less than 6F2.Type: GrantFiled: May 20, 2014Date of Patent: April 5, 2016Assignee: HGST, Inc.Inventor: Daniel R. Shepard
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Patent number: 9105340Abstract: A memory cell comprises a magnetic tunnel junction (MTJ) structure that includes a free layer coupled to a bit line and a pinned layer. A magnetic moment of the free layer is substantially parallel to a magnetic moment of the pinned layer in a first state and substantially antiparallel to the magnetic moment of the pinned layer in a second state. The pinned layer has a physical dimension to produce an offset magnetic field corresponding to a first switching current of the MTJ structure to enable switching between the first state and the second state when a first voltage is applied from the bit line to a source line coupled to an access transistor and a second switching current to enable switching between the second state and the first state when the first voltage is applied from the source line to the bit line.Type: GrantFiled: September 16, 2013Date of Patent: August 11, 2015Assignee: QUALCOMM IncorporatedInventors: Kangho Lee, Seung H. Kang, Xiachun Zhu
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Patent number: 9087986Abstract: A semiconductor memory device having a cell pattern formed on an interconnection and capable of reducing an interconnection resistance and a fabrication method thereof are provided. The semiconductor device includes a semiconductor substrate in which a cell area, a core area, and a peripheral area are defined and a bottom structure is formed, a conductive line formed on an entire structure of the semiconductor substrate, a memory cell pattern formed on the conductive line in the cell area, and a dummy conductive pattern formed on any one of the conductive line in the core area and the peripheral area.Type: GrantFiled: May 9, 2014Date of Patent: July 21, 2015Assignee: SK Hynix Inc.Inventor: Jang Uk Lee
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Patent number: 8976579Abstract: 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: GrantFiled: February 4, 2013Date of Patent: March 10, 2015Assignee: Kabushiki Kaisha ToshibaInventors: Hideaki Fukuzawa, Yoshiaki Fukuzumi, Hirofumi Morise, Akira Kikitsu
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Patent number: 8953368Abstract: A data reading method of a magnetic memory device includes generating read commands, supplying a read current to a selected magnetic memory element in a first direction and in turn in a second direction under different ones of the read commands, respectively, and sensing the magnitude of the read current flowing through the selected magnetic memory element to read data stored at the selected magnetic memory element.Type: GrantFiled: August 15, 2013Date of Patent: February 10, 2015Assignee: Samsung Electronics Co., Ltd.Inventor: Soo-Ho Cha
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Patent number: 8923040Abstract: A memory has magnetic tunnel junction elements with different resistances in different logic states, for bit positions in memory words accessed by a word line signal coupling each bit cell in the addressed word between a bit line and source line for that bit position. The bit lines and source lines are longer and shorter at different word line locations, causing a resistance body effect. A clamping transistor couples the bit line to a sensing circuit when reading, applying a current through the bit cell and producing a read voltage compared by the sensing circuit to a reference such as a comparable voltage from a reference bit cell circuit having a similar structure. A drive control varies an input to the switching transistor as a function of the word line location, e.g., by word line address, to offset the different bit and source line resistances.Type: GrantFiled: January 30, 2013Date of Patent: December 30, 2014Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.Inventors: Kai-Chun Lin, Hung-Chang Yu, Ku-Feng Lin, Yue-Der Chih
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Patent number: 8912013Abstract: A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a free layer and a spin torque enhancing layer. The spin torque enhancing layer includes a nano-oxide layer.Type: GrantFiled: December 19, 2012Date of Patent: December 16, 2014Assignee: QUALCOMM IncorporatedInventors: Xiaochun Zhu, Seung H. Kang, Xia Li
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Patent number: 8908428Abstract: An embodiment includes a three terminal magnetic element for a semiconductor memory device. The magnetic element includes a reference layer; a free layer; a barrier layer disposed between the reference layer and the free layer; a first electrode; an insulating layer disposed between the electrode and the free layer; and a second electrode coupled to sidewalls of the free layer.Type: GrantFiled: January 29, 2013Date of Patent: December 9, 2014Assignee: Samsung Electronics Co., Ltd.Inventors: Adrian E. Ong, Vladimir Nikitin, Mohamad Towfik Krounbi
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Patent number: 8861251Abstract: A semiconductor storage device includes a semiconductor substrate and an active area on the semiconductor substrate. A plurality of cell transistors are formed on the active area. A first bit line and a second bit line are paired with each other. A plurality of word lines intersect the first and second bit lines. A plurality of storage elements respectively has a first end electrically connected to a source or a drain of one of the cell transistors and a second end connected to the first or second bit line. Both of the first and second bit lines are connected to the same active area via the storage elements.Type: GrantFiled: March 19, 2012Date of Patent: October 14, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Susumu Shuto
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Patent number: 8841739Abstract: Embodiments of the invention implement DIOMEJ cells. In one embodiment, a DIOMEJ cell includes: an MEJ that includes, a ferromagnetic fixed layer, a ferromagnetic free layer, and a dielectric layer interposed between said fixed and free layers, where the fixed layer is magnetically polarized in a first direction, where the free layer has a first easy axis that is aligned with the first direction, and where the MEJ is configured such that when a potential difference is applied across it, the magnetic anisotropy of the free layer is altered such that the relative strength of the magnetic anisotropy along a second easy axis that is orthogonal to the first easy axis, as compared to the strength of the magnetic anisotropy along the first easy axis, is magnified for the duration of the application of the potential difference; and a diode, where the diode and the MEJ are arranged in series.Type: GrantFiled: September 9, 2013Date of Patent: September 23, 2014Assignee: The Regents of the University of CaliforniaInventors: Pedram Khalili Amiri, Kang L. Wang
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Patent number: 8780665Abstract: A method and system for providing a magnetic junction usable in a magnetic device are described. The magnetic junction includes a pinned layer, a nonmagnetic spacer layer, and a free layer. The nonmagnetic spacer layer is between the pinned layer and the free layer. The free layer has a magnetic anisotropy, at least a portion of which is a biaxial anisotropy. 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: GrantFiled: January 11, 2013Date of Patent: July 15, 2014Assignees: Samsung Electronics Co., Ltd., The Board of Trustees of the University of Alabama for and on Behalf of the University of AlabamaInventors: Dmytro Apalkov, William H. Butler
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Patent number: 8755220Abstract: 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: GrantFiled: July 16, 2013Date of Patent: June 17, 2014Assignee: International Business Machines CorporationInventors: John F. Bulzacchelli, William J. Gallagher, Mark B. Ketchen
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Patent number: 8724413Abstract: A multi-state current-switching magnetic memory element includes a stack of magnetic tunneling junction (MTJ) separated by a non-magnetic layer for storing more than one bit of information, wherein different levels of current applied to the memory element cause switching to different states.Type: GrantFiled: September 16, 2011Date of Patent: May 13, 2014Assignee: Avalanche Technology, Inc.Inventors: Rajiv Yadav Ranjan, Mahmud Assar, Parviz Keshtbod
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Patent number: 8724377Abstract: According to one embodiment, a memory device includes: a first signal line; a second signal line; a transistor; a first memory region; and a second memory region. The transistor controls a conduction of each of a current flowing between the first and the second signal lines and an opposite current. The first memory region has a first magnetic tunnel junction element. A magnetization direction thereof becomes parallel when a current flows in one direction, and the magnetization direction becomes antiparallel when a current in another direction. The second memory region has a second magnetic tunnel junction element. A magnetization direction thereof becomes parallel when a current flows in one direction, and becomes antiparallel when a current flows in another first direction.Type: GrantFiled: March 19, 2012Date of Patent: May 13, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Takaya Yamanaka, Susumu Shuto, Yoshiaki Asao
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Patent number: 8711632Abstract: The control circuit selects, as the first reference cell, the first memory cell having a maximum reading current supplied by turning on the first select transistor in a state in which resistance values of the first memory cells are all increased. The control circuit selects, as the second reference cell, the second memory cell having a maximum reading current supplied by turning on the second select transistor in a state in which resistance values of the second memory cells are all increased. The first reference-current setting circuit sets, as the first reference current, a current obtained by adding a first adjusting current to the reading current of the first reference cell. The second reference-current setting circuit sets, as the second reference current, a current obtained by adding a second adjusting current to the reading current of the second reference cell.Type: GrantFiled: March 21, 2012Date of Patent: April 29, 2014Assignee: Kabushiki Kaisha ToshibaInventor: Akira Katayama
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Patent number: 8687413Abstract: A magnetic memory unit includes a tunneling barrier separating a free magnetic element and a reference magnetic element. A first phonon glass electron crystal layer is disposed on a side opposing the tunneling barrier of either the free magnetic element or the reference magnetic element. A second phonon glass electron crystal layer also be disposed on a side opposing the tunneling barrier of either the free magnetic element or the reference magnetic element to provide a Peltier effect on the free magnetic element and the reference magnetic element.Type: GrantFiled: February 28, 2013Date of Patent: April 1, 2014Assignee: Seagate Technology LLCInventors: Yuankai Zheng, Haiwen Xi, Dimitar V. Dimitrov, Dexin Wang
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Patent number: 8681539Abstract: Spin-transfer torque memory includes a composite free magnetic element, a reference magnetic element having a magnetization orientation that is pinned in a reference direction, and an electrically insulating and non-magnetic tunneling barrier layer separating the composite free magnetic element from the magnetic reference element. The free magnetic element includes a hard magnetic layer exchanged coupled to a soft magnetic layer. The composite free magnetic element has a magnetization orientation that can change direction due to spin-torque transfer when a write current passes through the spin-transfer torque memory unit.Type: GrantFiled: April 15, 2013Date of Patent: March 25, 2014Assignee: Seagate Technology LLCInventors: Yuankai Zheng, Dimitar V. Dimitrov, Dexin Wang, Haiwen Xi, Kaizhong Gao, Olle Heinonen, Wenzhong Zhu
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Patent number: 8681536Abstract: A magnetic tunnel junction (MTJ) with direct contact is manufactured having lower resistances, improved yield, and simpler fabrication. The lower resistances improve both read and write processes in the MTJ. The MTJ layers are deposited on a bottom electrode aligned with the bottom metal. An etch stop layer may be deposited adjacent to the bottom metal to prevent overetch of an insulator surrounding the bottom metal. The bottom electrode is planarized before deposition of the MTJ layers to provide a substantially flat surface. Additionally, an underlayer may be deposited on the bottom electrode before the MTJ layers to promote desired characteristics of the MTJ.Type: GrantFiled: May 11, 2010Date of Patent: March 25, 2014Assignee: QUALCOMM IncorporatedInventors: Seung H. Kang, Xia Li, Wei-Chuan Chen, Kangho Lee, Xiaochun Zhu, Wah Nam Hsu
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Patent number: 8675401Abstract: A spin-transfer torque memory apparatus and self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage. Then applying a low resistance state polarized write current through the magnetic tunnel junction data cell, forming a low second resistance state magnetic tunnel junction data cell. A second read current is applied through the low second resistance state magnetic tunnel junction data cell to forming a second bit line read voltage. The method also includes comparing the first bit line read voltage with the second bit line read voltage to determine whether the first resistance state of the magnetic tunnel junction data cell was a high resistance state or low resistance state.Type: GrantFiled: March 19, 2013Date of Patent: March 18, 2014Assignee: Seagate Technology LLCInventors: Hai Li, Yiran Chen, Hongyue Liu, Kang Yong Kim, Dimitar V. Dimitrov, Henry F. Huang
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Patent number: 8553451Abstract: 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: GrantFiled: June 24, 2011Date of Patent: October 8, 2013Assignee: Micron Technology, Inc.Inventor: Jun Liu
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Patent number: 8547732Abstract: 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: GrantFiled: January 10, 2012Date of Patent: October 1, 2013Assignee: International Business Machines CorporationInventors: John F Bulzacchelli, William J Gallagher, Mark B Ketchen
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Patent number: 8526224Abstract: A compound magnetic data storage cell, applicable to spin-torque random access memory (ST-RAM), is disclosed. A magnetic data storage cell includes a magnetic storage element and two terminals communicatively connected to the magnetic storage element. The magnetic storage element is configured to yield any of at least three distinct magnetoresistance output levels, corresponding to stable magnetic configurations, in response to spin-momentum transfer inputs via the terminals.Type: GrantFiled: October 29, 2012Date of Patent: September 3, 2013Assignee: Seagate Technology LLCInventors: Thomas William Clinton, Werner Scholz
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Patent number: 8432731Abstract: A method, system, and apparatus magnetically coupled electrostatically shiftable memory device and method are disclosed. In one embodiment, a method includes electrostatically decoupling a separate structure and a surface that are magnetically coupled (e.g., an electrostatic force to decouple the separate structure and the surface is generated with an electrode), shifting the separate structure between the surface and a other surface with the electrostatic force (e.g., shifting the separate structure moves the entire separate structure), and magnetically coupling the separate structure to the other surface.Type: GrantFiled: September 29, 2008Date of Patent: April 30, 2013Inventors: Sridhar Kasichainula, Kishore Kasichainula, Mike Daneman
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Patent number: 8416614Abstract: A method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage. The magnetic tunnel junction data cell has a first resistance state. Then the method includes applying a second read current thorough the magnetic tunnel junction data cell having the first resistance state. The first read current is less than the second read current. Then the first bit line read voltage is compared with the second bit line read voltage to determine whether the first resistance state of the magnetic tunnel junction data cell was a high resistance state or low resistance state.Type: GrantFiled: January 12, 2012Date of Patent: April 9, 2013Assignee: Seagate Technology LLCInventors: Yiran Chen, Hai Li, Hongyue Liu, Ran Wang, Dimitar V. Dimitrov
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Patent number: 8411495Abstract: A spin-transfer torque memory apparatus and self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage, the magnetic tunnel junction data cell having a first resistance state and storing the first bit line read voltage in a first voltage storage device. Then applying a low resistance state polarized write current through the magnetic tunnel junction data cell, forming a low second resistance state magnetic tunnel junction data cell. A second read current is applied through the low second resistance state magnetic tunnel junction data cell to forming a second bit line read voltage. The second bit line read voltage is stored in a second voltage storage device.Type: GrantFiled: January 12, 2012Date of Patent: April 2, 2013Assignee: Seagate Technology LLCInventors: Hai Li, Yiran Chen, Hongyue Liu, Kang Yong Kim, Dimitar V. Dimitrov, Henry F. Huang
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Patent number: 8374048Abstract: A method and system for providing a magnetic junction usable in a magnetic device are described. The magnetic junction includes a pinned layer, a nonmagnetic spacer layer, and a free layer. The nonmagnetic spacer layer is between the pinned layer and the free layer. The free layer has a magnetic anisotropy, at least a portion of which is a biaxial anisotropy. 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: GrantFiled: August 11, 2010Date of Patent: February 12, 2013Assignee: Grandis, Inc.Inventor: Dmytro Apalkov
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Patent number: 8363459Abstract: A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a free layer and a spin torque enhancing layer. The spin torque enhancing layer includes a nano-oxide layer.Type: GrantFiled: June 11, 2009Date of Patent: January 29, 2013Assignee: QUALCOMM IncorporatedInventors: Xiaochun Zhu, Seung H. Kang, Xia Li
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Patent number: 8358531Abstract: Spin torque transfer magnetic random access memory devices configured to be programmed unidirectionally and methods of programming such devices. The devices include memory cells having two pinned layers and a free layer therebetween. By utilizing two pinned layers, the spin torque effect on the free layer from each of the two pinned layers, respectively, allows the memory cells to be programmed with unidirectional currents.Type: GrantFiled: January 24, 2012Date of Patent: January 22, 2013Assignee: Micron Technology, Inc.Inventors: Jun Liu, Gurtej Sandhu
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Patent number: 8347175Abstract: According to one embodiment, a magnetic memory includes a magnetoresistive effect element including a first magnetic layer invariable in magnetization direction, a second magnetic layer variable in magnetization direction, and an intermediate layer between the first magnetic layer and the second magnetic layer, an error detecting and correcting circuit which detects whether first data in the magnetoresistive effect element includes any error and which outputs error-corrected second data when the first data includes an error, a writing circuit which generates one of the first write current including a first pulse width and the second write current including a second pulse width greater than the first pulse width, and a control circuit which controls the writing circuit to pass the second write current through the magnetoresistive effect element when the second data is written into the magnetoresistive effect element.Type: GrantFiled: September 21, 2010Date of Patent: January 1, 2013Assignee: Kabushiki Kaisha ToshibaInventors: Sumio Ikegawa, Naoharu Shimomura, Kenji Tsuchida, Hiroaki Yoda
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Patent number: 8331139Abstract: Magnetic random access memory (MRAM) devices and techniques for use thereof are provided. In one aspect, a magnetic memory cell is provided. The magnetic memory cell comprises at least one fixed magnetic layer; at least one first free magnetic layer separated from the fixed magnetic layer by at least one barrier layer; at least one second free magnetic layer separated from the first free magnetic layer by at least one spacer layer; and at least one capping layer over a side of the second free magnetic layer opposite the spacer layer. One or more of the first free magnetic layer and the second free magnetic layer comprise at least one rare earth element, such that the at least one rare earth element makes up between about one percent and about 10 percent of one or more of the first free magnetic layer and the second free magnetic layer.Type: GrantFiled: February 28, 2011Date of Patent: December 11, 2012Assignee: International Business Machines CorporationInventors: William J. Gallagher, Daniel C. Worledge
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Patent number: 8325513Abstract: A compound magnetic data storage cell, applicable to spin-torque random access memory (ST-RAM), is disclosed. A magnetic data storage cell includes a magnetic storage element and two terminals communicatively connected to the magnetic storage element. The magnetic storage element is configured to yield any of at least three distinct magnetoresistance output levels, corresponding to stable magnetic configurations, in response to spin-momentum transfer inputs via the terminals.Type: GrantFiled: January 12, 2012Date of Patent: December 4, 2012Assignee: Seagate Technology LLCInventors: Thomas William Clinton, Werner Scholz
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Patent number: 8270204Abstract: Magnetic shift tracks or magnetic strips, to which application of a rotating magnetic field or by rotation of the strip itself allows accurate determination of domain wall movement. One particular embodiment is a method of determining a position of a domain wall in a magnetic strip. The method includes applying a rotating magnetic field to the magnetic strip, the magnetic field rotating around a longitudinal axis of the magnetic strip, and after applying the magnetic field, determining a displacement of the domain wall to a second position.Type: GrantFiled: July 9, 2009Date of Patent: September 18, 2012Assignee: Seagate Technology LLCInventors: Xiaobin Wang, Haiwen Xi, Yiran Chen, Yuan Yan, Jun Zheng
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Magnetoresistive random access memory (MRAM) with integrated magnetic film enhanced circuit elements
Patent number: 8248840Abstract: A Magnetoresistive Random Access Memory (MRAM) integrated circuit includes a substrate, a magnetic tunnel junction region, a magnetic circuit element, and an integrated magnetic material. The magnetic tunnel junction region is disposed on the substrate, and includes a first magnetic layer and a second magnetic layer separated by a tunnel barrier insulating layer. The magnetic circuit element region is disposed on the substrate, and includes a plurality of interconnected metal portions. The integrated magnetic material is disposed on the substrate adjacent to the plurality of interconnected metal portions.Type: GrantFiled: March 26, 2010Date of Patent: August 21, 2012Assignee: QUALCOMM IncorporatedInventors: Xia Li, Seung H. Kang, Xiaochun Zhu, Kangho Lee -
Patent number: 8233314Abstract: Apparatus and methods are disclosed that enable writing data on, and reading data of, multi-state elements having greater than two states. The elements may be made of magnetoplastic and/or magnetoelastic materials, including, for example, magnetic shape-memory alloy or other materials that couple magnetic and crystallographic states. The writing process is preferably conducted through the application of a magnetic field and/or a mechanical action. The reading process is preferably conducted through atomic-force microscopy, magnetic-force microscopy, spin-polarized electrons, magneto-optical Kerr effect, optical interferometry or other methods, or other methods/effects. The multifunctionality (crystallographic, magnetic, and shape states each representing a functionality) of the multi-state elements allows for simultaneous operations including read&write, sense&indicate, and sense&control.Type: GrantFiled: May 4, 2010Date of Patent: July 31, 2012Assignee: Boise State UniversityInventors: Peter Mullner, William B Knowlton
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Patent number: 8227896Abstract: Nitrogen-doped MgO insulating layers exhibit voltage controlled resistance states, e.g., a high resistance and a low resistance state. Patterned nano-devices on the 100 nm scale show highly reproducible switching characteristics. The voltage levels at which such devices are switched between the two resistance levels can be systematically lowered by increasing the nitrogen concentration. Similarly, the resistance of the high resistance state can be varied by varying the nitrogen concentration, and decreases by orders of magnitude by varying the nitrogen concentrations by a few percent. On the other hand, the resistance of the low resistance state is nearly insensitive to the nitrogen doping level. The resistance of single Mg50O50-xNx layer devices can be varied over a wide range by limiting the current that can be passed during the SET process. Associated data storage devices can be constructed.Type: GrantFiled: December 11, 2009Date of Patent: July 24, 2012Assignee: International Business Machines CorporationInventors: Xin Jiang, Stuart Stephen Papworth Parkin, Mahesh Govind Samant, Cheng-Han Yang
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Patent number: 8208288Abstract: 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: GrantFiled: March 27, 2008Date of Patent: June 26, 2012Assignee: International Business Machines CorporationInventors: John F. Bulzacchelli, William J. Gallagher, Mark B. Ketchen
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Patent number: 8203871Abstract: Spin torque magnetic logic devices that function as memory devices and that can be reconfigured or reprogrammed as desired. In some embodiments, the logic device is a single magnetic element, having a pinned layer, a free layer, and a barrier layer therebetween, or in other embodiments, the logic device has two magnetic elements in series. Two input currents can be applied through the element to configure or program the element. In use, logic input data, such as current, is passed through the programmed element, defining the resistance across the element and the resulting logic output. The magnetic logic device can be used for an all-function-in-one magnetic chip.Type: GrantFiled: November 30, 2010Date of Patent: June 19, 2012Assignee: Seagate Technology LLCInventors: Xiaohua Lou, Dimitar V. Dimitrov, Song S. Xue
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Patent number: 8159871Abstract: A magnetoresistive memory cell includes an MTJ device and a select transistor. The select transistor includes a first conduction-type semiconductor layer, a gate electrode formed by disposing a gate insulating layer on top of the semiconductor layer, and first and second diffusion regions formed in the semiconductor layer to be spaced apart from each other and to have a second conduction type. A part of the semiconductor layer between the first and second diffusion regions is formed as an electrically floating body region. By using a high-performance select transistor with a floating body effect, high integration of a magnetoresistive memory device may be achieved.Type: GrantFiled: July 22, 2009Date of Patent: April 17, 2012Assignee: Hynix Semiconductor Inc.Inventor: Sung Woong Chung
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Patent number: 8116122Abstract: A spin-transfer torque memory apparatus and self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage, the magnetic tunnel junction data cell having a first resistance state and storing the first bit line read voltage in a first voltage storage device. Then applying a low resistance state polarized write current through the magnetic tunnel junction data cell, forming a low second resistance state magnetic tunnel junction data cell. A second read current is applied through the low second resistance state magnetic tunnel junction data cell to forming a second bit line read voltage. The second bit line read voltage is stored in a second voltage storage device.Type: GrantFiled: June 27, 2008Date of Patent: February 14, 2012Assignee: Seagate Technology LLCInventors: Hai Li, Yiran Chen, Hongyue Liu, Kang Yong Kim, Dimitar V. Dimitrov, Henry F. Huang
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Patent number: 8116124Abstract: A compound magnetic data storage cell, applicable to spin-torque random access memory (ST-RAM), is disclosed. A magnetic data storage cell includes a magnetic storage element and two terminals communicatively connected to the magnetic storage element. The magnetic storage element is configured to yield any of at least three distinct magnetoresistance output levels, corresponding to stable magnetic configurations, in response to spin-momentum transfer inputs via the terminals.Type: GrantFiled: January 20, 2011Date of Patent: February 14, 2012Assignee: Seagate Technology LLCInventors: Thomas William Clinton, Werner Scholz
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Patent number: 8116123Abstract: A spin-transfer torque memory apparatus and non-destructive self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage and storing the first bit line read voltage in a first voltage storage device. The magnetic tunnel junction data cell has a first resistance state. Then the method includes applying a second read current thorough the magnetic tunnel junction data cell having the first resistance state and forming a second bit line read voltage and storing the second bit line read voltage in a second voltage storage device. The first read current is less than the second read current. Then the stored first bit line read voltage is compared with the stored second bit line read voltage to determine whether the first resistance state of the magnetic tunnel junction data cell was a high resistance state or low resistance state.Type: GrantFiled: June 27, 2008Date of Patent: February 14, 2012Assignee: Seagate Technology LLCInventors: Yiran Chen, Hai Li, Hongyue Liu, Ran Wang, Dimitar V. Dimitrov
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Patent number: RE46702Abstract: A memory according to an embodiment includes bit lines, word lines, source lines, magnetic tunnel junction elements and transistors that are serially connected between the bit lines and the source lines, respectively, and a sense amplifier that detects data stored in the magnetic tunnel junction elements. The semiconductor storage device includes multiplexers between the bit lines and the sense amplifier in order to select one of the bit lines to be connected to the sense amplifier, and write amplifiers that are located corresponding to memory cell blocks each of which includes memory cells each including the magnetic tunnel junction element and the transistor and are connected to the bit lines or connected via the multiplexers to the bit lines. To write data, the sense amplifier applies a write voltage to the bit lines and then the write amplifiers hold the write voltage.Type: GrantFiled: July 8, 2015Date of Patent: February 6, 2018Assignee: TOSHIBA MEMORY CORPORATIONInventors: Katsuhiko Hoya, Kenji Tsuchida