Magnetic Nonvolatile Memory Structures, E.g., Mram (epo) Patents (Class 257/E21.665)
  • Patent number: 8722543
    Abstract: A composite hard mask is disclosed that prevents build up of metal etch residue in a MRAM device during etch processes that define an MTJ shape. As a result, MTJ shape integrity is substantially improved. The hard mask has a lower non-magnetic spacer, a middle conductive layer, and an upper sacrificial dielectric layer. The non-magnetic spacer serves as an etch stop during a pattern transfer with fluorocarbon plasma through the conductive layer. A photoresist pattern is transferred through the dielectric layer with a first fluorocarbon etch. Then the photoresist is removed and a second fluorocarbon etch transfers the pattern through the conductive layer. The dielectric layer protects the top surface of the conductive layer during the second fluorocarbon etch and during a substantial portion of a third RIE step with a gas comprised of C, H, and O that transfers the pattern through the underlying MTJ layers.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: May 13, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Rodolfo Belen, Rongfu Xiao, Tom Zhong, Witold Kula, Chyu-Jiuh Torng
  • Patent number: 8716819
    Abstract: According to one embodiment, a magnetic random access memory includes a plurality of magnetoresistance elements. The plurality of magnetoresistance elements each include a recording layer having magnetic anisotropy perpendicular to a film surface, and a variable magnetization direction, a reference layer having magnetic anisotropy perpendicular to a film surface, and an invariable magnetization direction, and a first nonmagnetic layer formed between the recording layer and the reference layer. The recording layer is physically separated for each of the plurality of magnetoresistance elements. The reference layer and the first nonmagnetic layer continuously extend over the plurality of magnetoresistance elements.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: May 6, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Naoharu Shimomura, Tsuneo Inaba
  • Patent number: 8710602
    Abstract: A method and system provide a magnetic junction usable in a magnetic device. The magnetic junction includes a pinned layer, a nonmagnetic spacer layer, a free layer, at least one insulating layer, and at least one magnetic insertion layer adjoining the at least one insulating layer. The nonmagnetic spacer layer is between the pinned layer and the free layer. The at least one insulating layer is adjacent to at least one of the free layer and the pinned layer. The at least one magnetic insertion layer adjoins the at least one insulating layer. In some aspects, the insulating layer(s) include at least one of magnesium oxide, aluminum oxide, tantalum oxide, ruthenium oxide, titanium oxide, and nickel oxide 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: December 20, 2011
    Date of Patent: April 29, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xueti Tang, Dmytro Apalkov, Steven M. Watts, Kiseok Moon, Vladimir Nikitin
  • Patent number: 8704319
    Abstract: A method and system provide a magnetic junction usable in a magnetic device. The magnetic junction includes a pinned layer, a nonmagnetic spacer layer, a free layer, and at least one damping reduction layer. The free layer has an intrinsic damping constant. The nonmagnetic spacer layer is between the pinned layer and the free layer. The at least one damping reduction layer is adjacent to at least a portion of the free layer and configured to reduce the intrinsic damping constant of the free layer. 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: December 20, 2011
    Date of Patent: April 22, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xueti Tang, Vladimir Nikitin, Dmytro Apalkov, Kiseok Moon, Steven M. Watts
  • Publication number: 20140103469
    Abstract: A magnetic element is disclosed wherein a composite seed layer such as TaN/Mg enhances perpendicular magnetic anisotropy (PMA) in an overlying magnetic layer that may be a reference layer, free layer, or dipole layer. The first seed layer is selected from one or more of Ta, Zr, Nb, TaN, ZrN, NbN, and Ru. The second seed layer is selected from one or more of Mg, Sr, Ti, Al, V, Hf, B, and Si. A growth promoting layer made of NiCr or an alloy thereof may be inserted between the seed layer and magnetic layer. The magnetic element has thermal stability to at least 400° C.
    Type: Application
    Filed: October 11, 2012
    Publication date: April 17, 2014
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Guenole Jan, Ru-Ying Tong
  • Patent number: 8685756
    Abstract: A dual tunnel barrier magnetic element has a free magnetic layer positioned between first and second tunnel barriers and an electrode over the second tunnel barrier. A two step etch process allows for forming an encapsulation material on a side wall of the electrode and the second tunnel barrier subsequent to the first etch for preventing damage to the first tunnel barrier when performing the second etch to remove a portion of the free layer.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 1, 2014
    Assignee: EverSpin Technologies, Inc.
    Inventors: Sanjeev Aggarwal, Kerry Nagel, Jason Janesky
  • Patent number: 8687414
    Abstract: A magnetic memory cell includes: a magnetization recording layer; and a magnetic tunneling junction section. The magnetization recording layer includes a ferromagnetic layer with perpendicular magnetic anisotropy. The magnetic tunneling junction section is used for reading information in the magnetization recording layer. The magnetization recording layer includes two domain wall moving areas.
    Type: Grant
    Filed: December 24, 2009
    Date of Patent: April 1, 2014
    Assignee: NEC Corporation
    Inventors: Kiyokazu Nagahara, Shunsuke Fukami, Nobuyuki Ishiwata, Tetsuhiro Suzuki, Norikazu Ohshima
  • Patent number: 8681536
    Abstract: 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: Grant
    Filed: May 11, 2010
    Date of Patent: March 25, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Seung H. Kang, Xia Li, Wei-Chuan Chen, Kangho Lee, Xiaochun Zhu, Wah Nam Hsu
  • Patent number: 8673654
    Abstract: An MRAM structure is disclosed in which the bottom electrode has an amorphous TaN capping layer to consistently provide smooth and dense growth for AFM, pinned, tunnel barrier, and free layers in an overlying MTJ. Unlike a conventional Ta capping layer, TaN is oxidation resistant and has high resistivity to avoid shunting of a sense current caused by redeposition of the capping layer on the sidewalls of the tunnel barrier layer. Alternatively, the ?-TaN layer is the seed layer in the MTJ. Furthermore, the seed layer may be a composite layer comprised of a NiCr, NiFe, or NiFeCr layer on the ?-TaN layer. An ?-TaN capping layer or seed layer can also be used in a TMR read head. An MTJ formed on an ?-TaN capping layer has a high MR ratio, high Vb, and a RA similar to results obtained from MTJs based on an optimized Ta capping layer.
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: March 18, 2014
    Assignee: Headway Technologies, Inc.
    Inventors: Liubo Hong, Cheng Horng, Mao-Min Chen, Ru-Yin Tong
  • Patent number: 8664010
    Abstract: An MTJ element is formed in a wiring layer located in a lower tier and yet application of heat to the MTJ element is suppressed. A first insulating layer is formed over a substrate. Subsequently, the MTJ element is formed over the first insulating layer. After that a first wiring is formed over the MTJ element. Thereafter, a second insulating layer is formed over the first wiring. Then a second wiring is formed in the superficial layer of the second insulating layer. The second wiring is heat treated by photoirradiation. A shield conductor is formed at the step of forming the second wiring.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: March 4, 2014
    Assignee: Renesas Electronics Corporation
    Inventor: Yoshihisa Matsubara
  • Patent number: 8652856
    Abstract: Disclosed herein is a method of forming electronic device having thin-film components by using trenches. One or more of thin-film components is formed by depositing a thin-film in the trench followed by processing the deposited thin-film to have the desired thickness.
    Type: Grant
    Filed: March 21, 2013
    Date of Patent: February 18, 2014
    Assignee: Crocus Technology Inc.
    Inventors: Jean Pierre Nozieres, Jason Reid
  • Patent number: 8647891
    Abstract: A sensor and fabrication process are provided for forming reference layers with substantially orthogonal magnetization directions having zero offset with a small compensation angle. An exemplary embodiment includes a sensor layer stack of a magnetoresistive thin-film based magnetic field sensor, the sensor layer stack comprising a pinning layer; a pinned layer including a layer of amorphous material over the pinning layer, and a first layer of crystalline material over the layer of amorphous material; a nonmagnetic coupling layer over the pinned layer; a fixed layer over the nonmagnetic coupling layer; a tunnel barrier over the fixed layer; and a sense layer over the nonmagnetic intermediate layer. Another embodiment includes a sensor layer stack where a pinned layer including two crystalline layers separated by a amorphous layer.
    Type: Grant
    Filed: June 4, 2013
    Date of Patent: February 11, 2014
    Assignee: Everspin Technologies, Inc.
    Inventors: Jijun Sun, Phillip Mather, Srinivas Pietambaram, Jon Slaughter, Renu Whig, Nicholas Rizzo
  • Patent number: 8644063
    Abstract: An electronic device manufacturing process includes depositing a bottom electrode layer. Then an electronic device is fabricated on the bottom electrode layer. Patterning of the bottom electrode layer is performed after fabricating the electronic device and in a separate process from patterning a top electrode. A first dielectric layer is then deposited on the electronic device and the bottom electrode layer followed by a top electrode layer. The top electrode is then patterned in a separate process from the bottom electrode. Separately patterning the top and bottom electrodes improves yields by reducing voids in the dielectric material between electronic devices. One electronic device the manufacturing process is well-suited for is magnetic tunnel junctions (MTJs).
    Type: Grant
    Filed: May 6, 2013
    Date of Patent: February 4, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xia Li, Seung H. Kang
  • Publication number: 20140004625
    Abstract: A method of fabricating a self-aligning magnetic tunnel junction the method includes patterning a lithographic strip on a second magnetic material deposited on a first magnetic material that is disposed on a substrate, forming a top magnetic strip by etching an exposed portion of the second magnetic material, patterning a nanowire and a magnetic reference layer island over the substrate and forming the nanowire and the magnetic reference layer island by etching an exposed portion of the first magnetic layer and an exposed portion of the top magnetic strip, wherein an interface between the magnetic nanowire and the magnetic reference layer island is an magnetic tunnel junction aligned with a width of the nanowire.
    Type: Application
    Filed: July 23, 2012
    Publication date: January 2, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Anthony J. Annunziata, Michael C. Gaidis
  • Patent number: 8619467
    Abstract: Multi-period structures exhibiting giant magnetoresistance (GMR) are described in which the exchange coupling across the active interfaces of the structure is ferromagnetic.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: December 31, 2013
    Assignee: Integrated Magnetoelectronics
    Inventors: E. James Torok, Richard Spitzer, David L. Fleming, Edward Wuori
  • Publication number: 20130334630
    Abstract: Methods of forming magnetic memory cells are disclosed. Magnetic and non-magnetic materials are formed into a primal precursor structure in an initial stress state of essentially no strain, compressive strain, or tensile strain. A stress-compensating material, e.g., a non-sacrificial, conductive material, is formed to be disposed on the primal precursor structure to form a stress-compensated precursor structure in a net beneficial stress state. Thereafter, the stress-compensated precursor structure may be patterned to form a cell core of a memory cell. The net beneficial stress state of the stress-compensated precursor structure lends to formation of one or more magnetic regions, in the cell core, exhibiting a vertical magnetic orientation without deteriorating a magnetic strength of the one or more magnetic regions. Also disclosed are memory cells, memory cell structures, semiconductor device structures, and spin torque transfer magnetic random access memory (STT-MRAM) systems.
    Type: Application
    Filed: June 19, 2012
    Publication date: December 19, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Witold Kula, Gurtej S. Sandhu, Stephen J. Kramer
  • Patent number: 8609262
    Abstract: A STT-RAM MTJ is disclosed with a MgO tunnel barrier formed by natural oxidation and containing an oxygen surfactant layer to form a more uniform MgO layer and lower breakdown distribution percent. A CoFeB/NCC/CoFeB composite free layer with a middle nanocurrent channel layer minimizes Jc0 while enabling thermal stability, write voltage, read voltage, and Hc values that satisfy 64 Mb design requirements. The NCC layer has RM grains in an insulator matrix where R is Co, Fe, or Ni, and M is a metal such as Si or Al. NCC thickness is maintained around the minimum RM grain size to avoid RM granules not having sufficient diameter to bridge the distance between upper and lower CoFeB layers. A second NCC layer and third CoFeB layer may be included in the free layer or a second NCC layer may be inserted below the Ru capping layer.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: December 17, 2013
    Assignee: MagIC Technologies, Inc.
    Inventors: Cheng T. Horng, Ru-Ying Tong, Guangli Liu, Robert Beach, Witold Kula, Tai Min
  • Patent number: 8604572
    Abstract: A magnetic tunnel junction device comprises a fixed magnetic layer having a first side and a second side, the fixed magnetic layer having a magnetic anisotropy that is out of the film plane of the fixed magnetic layer; a stack of a plurality of bilayers adjacent to the first side of the fixed magnetic layer, each bilayer comprising a first layer comprising at least one of cobalt, iron, a CoFeB alloy, or a CoB alloy and a second layer in contact with the first layer, the second layer comprising palladium or platinum, wherein the plurality of bilayers has a magnetic anisotropy that is out of the film plane of each of the bilayers, wherein the fixed magnetic layer is exchange coupled to the stack of the plurality of bilayers, and a tunnel barrier layer in contact with the second side of the fixed magnetic layer.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: December 10, 2013
    Assignee: Regents of the University of Minnesota
    Inventors: Jian-Ping Wang, Md. Tofizur Rahman
  • Publication number: 20130313664
    Abstract: A resistive memory device capable of minimizing operation current and a fabrication method thereof are provided. The resistive memory device includes an access device, a heating electrode formed on the access device and serving as a magnetoresistance device, and a variable resistance material formed on the heating electrode.
    Type: Application
    Filed: August 31, 2012
    Publication date: November 28, 2013
    Inventors: Ha Chang JUNG, Jung Taik CHEONG
  • Patent number: 8592927
    Abstract: A magnetic element is disclosed that has a composite free layer with a FM1/moment diluting/FM2 configuration wherein FM1 and FM2 are magnetic layers made of one or more of Co, Fe, Ni, and B and the moment diluting layer is used to reduce the perpendicular demagnetizing field. As a result, lower resistance x area product and higher thermal stability are realized when perpendicular surface anisotropy dominates shape anisotropy to give a magnetization perpendicular to the planes of the FM1, FM2 layers. The moment diluting layer may be a non-magnetic metal like Ta or a CoFe alloy with a doped non-magnetic metal. A perpendicular Hk enhancing layer interfaces with the FM2 layer and may be an oxide to increase the perpendicular anisotropy field in the FM2 layer. The magnetic element may be part of a spintronic device or serve as a propagation medium in a domain wall motion device.
    Type: Grant
    Filed: May 4, 2011
    Date of Patent: November 26, 2013
    Assignee: MagIC Technologies, Inc.
    Inventors: Guenole Jan, Ru Ying Tong, Witold Kula
  • Patent number: 8587043
    Abstract: According to one embodiment, a magnetoresistive random access memory includes a magnetoresistive element in a memory cell, the magnetoresistive element including a first metal magnetic layer, a second metal magnetic layer, and an insulation layer interposed between the first and second metal magnetic layers. An area of each of the first and second metal magnetic layers is smaller than an area of the insulation layer.
    Type: Grant
    Filed: March 18, 2011
    Date of Patent: November 19, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuaki Natori, Koji Yamakawa, Daisuke Ikeno
  • Patent number: 8581346
    Abstract: A semiconductor memory device includes a first conductive line, a second conductive line crossing over the first conductive line, a resistance variation part disposed at a position in which the second conductive line intersects with the first conductive line and electrically connected to the first conductive line and the second conductive line and a mechanical switch disposed between the resistance variation part and the second conductive line. The mechanical switch includes a nanotube.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: November 12, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: HongSik Yoon, Jinshi Zhao, Ingyu Baek, Hyunjun Sim, Minyoung Park
  • 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
  • Publication number: 20130277778
    Abstract: This description relates to a method for fabricating a magnetoresistive random access memory (MRAM) device having a plurality of magnetic tunnel junction (MTJ) units. The method includes forming a bottom conductive layer, forming an anti-ferromagnetic layer and forming a tunnel layer over the bottom conductive layer and the anti-ferromagnetic layer. The method further includes forming a free magnetic layer, having a magnetic moment aligned in a direction that is adjustable by applying an electromagnetic field, over the tunnel layer and forming a top conductive layer over the free magnetic layer. The method further includes performing at least one lithographic process to remove portions of the bottom conductive layer, the anti-ferromagnetic layer, the tunnel layer, the free magnetic layer and the top conductive layer that is uncovered by the photoresist layer until the bottom conductive layer is exposed and removing portions of at least one sidewall of the MTJ unit.
    Type: Application
    Filed: April 20, 2012
    Publication date: October 24, 2013
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Chern-Yow HSU, Shih-Chang LIU, Chia-Shiung TSAI
  • Patent number: 8557610
    Abstract: Methods and apparatus for shielding a shielding a non-volatile memory, such as shielding a magnetic tunnel junction (MTJ) device from a magnetic flux are provided. In an example, a shielding layer is formed adjacent to an electrode of an MTJ device, such that the shielding layer substantially surrounds a surface of the electrode, and a metal line is coupled to the shielding layer. The metal line can be coupled to the shielding layer by a via.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: October 15, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Wei-Chuan Chen, Xia Li, Seung H. Kang
  • 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: 8546263
    Abstract: Embodiments of the invention generally relate to methods for fabricating devices on semiconductor substrates. More specifically, embodiments of the invention relate to methods of patterning magnetic materials. Certain embodiments described herein use a reducing chemistry containing a hydrogen gas or hydrogen containing gas with an optional dilution gas at temperatures ranging from 20 to 300 degrees Celsius at a substrate bias less than 1,000 DC voltage to reduce the amount of sputtering and redeposition. Exemplary hydrogen containing gases which may be used with the embodiments described herein include NH3, H2, CH4, C2H4, SiH4, and H2S. It has been found that patterning a magnetic tunnel junction with an oxidizer-free gas mixture comprising hydrogen maintains the integrity of the magnetic tunnel junction without producing harmful conductive residue.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: October 1, 2013
    Assignee: Applied Materials, Inc.
    Inventors: Olivier Joubert, Benjamin Schwarz, Jérémy Gilbert Maurice Pereira, Kevin Menguelti, Erwine Maude Pargon, Maxime Darnon
  • Publication number: 20130250661
    Abstract: Memory cells including cell cores having free regions are disclosed. The free regions exhibit a strain that affects a magnetization orientation within the cell core. A stressor structure may exert a stress upon at least a portion of the cell core to effect the strain state of the free region. Also disclosed are semiconductor device structures and systems including such memory cells as well as methods for forming such memory cells.
    Type: Application
    Filed: March 22, 2012
    Publication date: September 26, 2013
    Applicant: Micron Technology, Inc.
    Inventors: Gurtej S. Sandhu, Wayne I. Kinney
  • Publication number: 20130250662
    Abstract: A magnetoresistive random access memory (MRAM) die may include an MRAM cell, a reservoir defined by the MRAM die, and a chemical disposed in the reservoir. At least one boundary of the reservoir may be configured to be damaged in response to attempted tampering with the MRAM die, such that at least some of the chemical is released from the reservoir when the at least one boundary of the reservoir is damaged. In some examples, at least some of the chemical is configured to contact and alter or damage at least a portion of the MRAM cell when the chemical is released from the reservoir.
    Type: Application
    Filed: March 26, 2012
    Publication date: September 26, 2013
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Romney R. Katti, James L. Tucker, Anuj Kohli
  • Patent number: 8542519
    Abstract: According to one embodiment, a semiconductor memory device is disclosed. The device includes MOSFET1 and MOSFET2 arranged in a first direction, variable resistive element (hereafter R1) above MOSFET1 and MOSFET2, a lower end of the R1 being connected to drains of MOSFET1 and MOSFET2, MOSFET3 and MOSFET4 arranged in the first direction, variable resistive element (hereafter R2) above MOSFET3 and MOSFET4, and a lower end of the R2 being connected to drains of MOSFET3 and MOSFET4. The device further includes first wiring line extending in the first direction and connected to sources of MOSFET1 and MOSFET2, second wiring line extending in the first direction and connected to sources of MOSFET3 and MOSFET4, upper electrode connecting upper end of the R1 and upper end of the R2, and third wiring line extending in the first direction and connected to the upper electrode.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: September 24, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Asao, Takeshi Kajiyama, Kuniaki Sugiura
  • Publication number: 20130244342
    Abstract: A magnetic tunnel junction (MTJ) structure is provided over a device wherein the MTJ comprises a tunnel barrier layer between a free layer and a pinned layer; and a top and bottom electrode inside the MTJ structure. A hard mask layer is formed on the top electrode. The hard mask layer, top electrode, free layer, tunnel barrier layer, and pinned layer are patterned to define the magnetic tunnel junction (MTJ) structures. A first dielectric layer is deposited over the MTJ structures and planarized to expose the top electrode. Thereafter, the top electrode and free layer are patterned. A second dielectric layer is deposited over the MTJ structures and planarized to expose the top electrode. A third dielectric layer is deposited over the MTJ structures and a metal line contact is formed through the third dielectric layer to the top electrode to complete fabrication of the magnetic device.
    Type: Application
    Filed: March 14, 2012
    Publication date: September 19, 2013
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Yu-Jen WANG, Yuan-Tung CHIN
  • Publication number: 20130242646
    Abstract: An MRAM die may include a first write line, a second write line, an MRAM cell disposed between the first write line and the second write line, and a magnetic security structure adjacent to the MRAM cell. The magnetic security structure may include a permanent magnetic layer and a soft magnetic layer.
    Type: Application
    Filed: March 13, 2012
    Publication date: September 19, 2013
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Romney R. Katti, James L. Tucker, Anuj Kohli
  • Patent number: 8535953
    Abstract: Processes for selectively patterning a magnetic film structure generally include selectively etching an exposed portion of a freelayer disposed on a tunnel barrier layer by a wet process, which includes exposing the freelayer to an etchant solution comprising at least one acid and an organophosphorus acid inhibitor or salt thereof, stopping on the tunnel barrier layer.
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: September 17, 2013
    Assignee: International Business Machines Corporation
    Inventors: David W. Abraham, Solomon Assefa, Eugene J. O'Sullivan
  • Patent number: 8535952
    Abstract: In accordance with a method of the present invention, a method of manufacturing a magnetic random access memory (MRAM) cell and a corresponding structure thereof are disclosed to include a multi-stage manufacturing process. The multi-stage manufacturing process includes performing a front end on-line (FEOL) stage to manufacture logic and non-magnetic portions of the memory cell by forming an intermediate interlayer dielectric (ILD) layer, forming intermediate metal pillars embedded in the intermediate ILD layer, depositing a conductive metal cap on top of the intermediate ILD layer and the metal pillars, performing magnetic fabrication stage to make a magnetic material portion of the memory cell being manufactured, and performing back end on-line (BEOL) stage to make metal and contacts of the memory cell being manufactured.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: September 17, 2013
    Assignee: Avalanche Technology, Inc.
    Inventors: Rajiv Yadav Ranjan, Parviz Keshtbod, Roger Klas Malmhall
  • Patent number: 8536669
    Abstract: According to an embodiment of the invention, a magnetic tunnel junction (MTJ) element includes a reference ferromagnetic layer, a storage ferromagnetic layer, and an insulating layer. The storage ferromagnetic layer includes a CoFeB sub-layer coupled to a CoFe sub-layer and/or a NiFe sub-layer through a non-magnetic sub-layer. The insulating layer is disposed between the reference and storage ferromagnetic layers.
    Type: Grant
    Filed: January 13, 2009
    Date of Patent: September 17, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xiaochun Zhu, Xia Li, Seung H. Kang
  • Publication number: 20130228882
    Abstract: Methods and apparatuses for a magnetic tunnel junction (MTJ) which can be used in as a magnetic random access memory cell are disclosed. The MTJ comprises a free layer and an insulator layer. The MTJ further comprises a pinned layer with a first region, a second region, and a third region. The second region is of a first length and of a first thickness, and the first region and the third region are of a second length and of a second thickness. A ratio of the first thickness to the second thickness may be larger than 1.2. A ratio of the second length to the first length is larger than 0.5. The first thickness may be larger than a spin diffusion length of a material for the pinned layer. So formed MTJ results in increased tunneling magnetic resistance ratio and reduced critical switch current of the MTJ.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 5, 2013
    Applicant: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Kai-Wen Cheng, Chwen Yu, Chih-Ming Chen
  • Patent number: 8524510
    Abstract: A method for manufacturing a magnetic memory chip device comprises the steps of: writing information in each of a plurality of magnetic memory chips formed on a silicon wafer; adhering a high magnetic permeability plate on a back face of the silicon wafer after writing information, the high magnetic permeability plate having a higher magnetic permeability than silicon and having a thickness of 50 um or more; dicing the silicon wafer into respective magnetic memory chips after adhering the high magnetic permeability plate.
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: September 3, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Kazuyuki Misumi, Masahiro Shimizu, Tsuyoshi Koga, Tatsuhiko Akiyama, Tomohiro Murakami
  • Publication number: 20130221459
    Abstract: A magnetic element is disclosed wherein first and second interfaces of a free layer with a perpendicular Hk enhancing layer and tunnel barrier, respectively, produce enhanced surface perpendicular anisotropy to increase thermal stability in a magnetic tunnel junction (MTJ). The free layer may be a single layer or a composite and is comprised of one or more glassing agents that have a first concentration in a middle portion thereof and a second concentration less than the first concentration in regions near first and second interfaces. As a result, a CoFeB free layer, for example, selectively crystallizes along first and second interfaces but maintains an amorphous character in a middle region containing a glass agent providing the annealing temperature is less than the crystallization temperature of the middle region. The magnetic element may be part of a spintronic device or serve as a propagation medium in a domain wall motion device.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 29, 2013
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Guenole Jan, Yu-Jen Wang, Tong Ru Ying
  • Patent number: 8519376
    Abstract: Nonvolatile resistive memory devices are disclosed. In some embodiments, the memory devices comprise multilayer structures including electrodes, one or more resistive storage layers, and separation layers. The separation layers insulate the resistive storage layers to prevent charge leakage from the storage layers and allow for the use of thin resistive storage layers. In some embodiments, the nonvolatile resistive memory device includes a metallic multilayer comprising two metallic layers about an interlayer. A dopant at an interface of the interlayer and metallic layers can provide a switchable electric field within the multilayer.
    Type: Grant
    Filed: October 27, 2009
    Date of Patent: August 27, 2013
    Assignee: Seagate Technology LLC
    Inventors: Dimitar Velikov Dimitrov, Insik Jin, Haiwen Xi
  • Patent number: 8519497
    Abstract: A device comprising a diblock copolymer mask for fabricating a magnetoresistive random access memory (MRAM) includes a magnetic layer; a mask formed on the magnetic layer; a template formed on the mask; and the diblock copolymer mask, the diblock copolymer mask comprising a first plurality of uniform shapes formed on and registered to the template.
    Type: Grant
    Filed: February 15, 2012
    Date of Patent: August 27, 2013
    Assignee: International Business Machines Corporation
    Inventor: Michael C. Gaidis
  • Patent number: 8502331
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including perpendicular anisotropy to a film surface and an invariable magnetization direction, the first magnetic layer having a magnetic film including an element selected from a first group including Tb, Gd, and Dy and an element selected from a second group including Co and Fe, a second magnetic layer including perpendicular magnetic anisotropy to the film surface and a variable magnetization direction, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer. The magnetic film includes amorphous phases and crystals whose particle sizes are 0.5 nm or more.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: August 6, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Tadaomi Daibou, Yutaka Hashimoto, Masaru Tokou, Tadashi Kai, Makoto Nagamine, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando
  • Patent number: 8497559
    Abstract: A CPP MTJ MRAM unit cell utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer. The strength of the switching field, Hs of the cell is controlled by the magnetic anisotropy of the cell which, in turn, is controlled by a combination of the shape anisotropy and the stress and magnetostriction of the cell free layer. The coefficient of magnetostriction of the free layer can be adjusted by methods such as adding Nb or Hf to alloys of Ni, Fe, Co and B or by forming the free layer as a lamination of layers having different values of their coefficients of magnetostriction. Thus, by tuning the coefficient of magnetostriction of the cell free layer it is possible to produce a switching field of sufficient magnitude to render the cell thermally stable while maintaining a desirable switching current.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: July 30, 2013
    Assignee: MagIC Technologies, Inc.
    Inventors: Tai Min, Po Kang Wang
  • Publication number: 20130187247
    Abstract: A spin-torque transfer (STT) magnetic tunnel junction (MTJ) memory includes a unitary fixed magnetic layer, a magnetic barrier layer on the unitary fixed magnetic layer, a free magnetic layer having a plurality of free magnetic islands on the magnetic barrier layer, and a cap layer overlying the free magnetic layer. Also a method of forming an STT-MTJ memory.
    Type: Application
    Filed: January 23, 2012
    Publication date: July 25, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Wenqing WU, Sean Li, Xiaochun Zhu, Raghu Sagar Madala, Seung H. Kang, Kendrick H. Yuen
  • Patent number: 8487390
    Abstract: A magnetic memory element that has a stress-induced magnetic anisotropy. The memory element has a ferromagnetic free layer having a switchable magnetization orientation switchable, a ferromagnetic reference layer having a pinned magnetization orientation, and a non-magnetic spacer layer therebetween. The free layer may be circular, essentially circular or nearly circular.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: July 16, 2013
    Assignee: Seagate Technology LLC
    Inventors: Dimitar V. Dimitrov, Ivan Petrov Ivanov, Shuiyuan Huang, Antoine Khoueir, Brian Lee, John Daniel Stricklin, Olle Gunnar Heinonen, Insik Jin
  • Publication number: 20130175644
    Abstract: A STT-RAM MTJ is disclosed with a composite tunnel barrier comprised of a CoMgO layer that contacts a pinned layer and a MgO layer which contacts a free layer. A CoMg layer with a Co content between 20 and 40 atomic % is deposited on the pinned layer and is then oxidized to produce Co nanoconstrictions within a MgO insulator matrix. The nanoconstrictions control electromigration of Co into an adjoining MgO layer. The free layer may comprise a nanocurrent channel (NCC) layer such as FeSiO or a moment dilution layer such as Ta between two ferromagnetic layers. Furthermore, a second CoMgO layer or a CoMgO/MgO composite may serve as a perpendicular Hk enhancing layer formed between the free layer and a cap layer. One or both of the pinned layer and free layer may exhibit in-plane anisotropy or perpendicular magnetic anisotropy.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 11, 2013
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Cheng T. Horng, Ru-Ying Tong
  • Patent number: 8477531
    Abstract: A semiconductor memory device includes a magnetic tunneling junction (MTJ); and a magnetic feature aligned with the MTJ and approximate the MTJ. When viewed in a direction perpendicular to the MTJ and the magnetic feature, the magnetic feature has a disk shape, and the MTJ has an elliptical shape and is positioned within the disk shape.
    Type: Grant
    Filed: December 15, 2010
    Date of Patent: July 2, 2013
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chwen Yu, Tien-Wei Chiang
  • Patent number: 8476721
    Abstract: A transistor device includes a magnetic field source adapted to deflect a flow of free electron carriers within a channel of the device, between a source region and a drain region thereof. According to preferred configurations, the magnetic field source includes a magnetic material layer extending over a side of the channel that is opposite a gate electrode of the transistor device.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: July 2, 2013
    Assignee: Seagate Technology LLC
    Inventors: Yang Li, Insik Jin, Harry Liu, Song S. Xue, Shuiyuan Huang, Michael X. Tang
  • Patent number: 8455965
    Abstract: An electronic device manufacturing process includes depositing a bottom electrode layer. Then an electronic device is fabricated on the bottom electrode layer. Patterning of the bottom electrode layer is performed after fabricating the electronic device and in a separate process from patterning a top electrode. A first dielectric layer is then deposited on the electronic device and the bottom electrode layer followed by a top electrode layer. The top electrode is then patterned in a separate process from the bottom electrode. Separately patterning the top and bottom electrodes improves yields by reducing voids in the dielectric material between electronic devices. One electronic device the manufacturing process is well-suited for is magnetic tunnel junctions (MTJs).
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: June 4, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xia Li, Seung H. Kang
  • Patent number: 8456883
    Abstract: CMOS devices are provided in a substrate having a topmost metal layer comprising metal landing pads and metal connecting pads. A plurality of magnetic tunnel junction (MTJ) structures are provided over the CMOS devices and connected to the metal landing pads. The MTJ structures are covered with a dielectric layer that is polished until the MTJ structures are exposed. Openings are etched in the dielectric layer to the metal connecting pads. A seed layer is deposited over the dielectric layer and on inside walls and bottom of the openings. A copper layer is plated on the seed layer until the copper layer fills the openings. The copper layer is etched back and the seed layer is removed. Thereafter, an aluminum layer is deposited over the dielectric layer, contacting both the copper layer and the MTJ structures, and patterned to form a bit line.
    Type: Grant
    Filed: May 29, 2012
    Date of Patent: June 4, 2013
    Assignee: Headway Technologies, Inc.
    Inventor: Daniel Liu
  • Patent number: 8455267
    Abstract: A magnetic tunnel junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, a method is disclosed that includes forming a magnetic tunnel junction (MTJ) device on a structure that includes a bottom cap layer and a bottom metal-filled trench having a normal axis, the magnetic tunnel junction device including a bottom electrode, magnetic tunnel junction layers, a magnetic tunnel junction seal layer, a top electrode, and a logic cap layer, the magnetic tunnel junction device having an MTJ axis that is offset from the normal axis.
    Type: Grant
    Filed: May 14, 2009
    Date of Patent: June 4, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xia Li, Seung H. Kang, Xiaochun Zhu