Resistive Patents (Class 365/100)
  • Patent number: 7924598
    Abstract: A nonvolatile semiconductor memory according to an aspect of the invention includes a memory cell array and a power supply circuit. The memory cell array includes memory cells each having an insulating film and being programmed to store information by inflicting an electric stress on the insulating film to break the insulating film. The power supply circuit supplies to the memory cell a program voltage for the electric stress depending on a negative temperature coefficient the electric stress.
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: April 12, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mariko Hase, Toshimasa Namekawa
  • Patent number: 7920402
    Abstract: A resistance variable memory apparatus (100) of the present invention is a resistance variable memory apparatus (100) using a resistance variable element (22) transitioning between plural resistance states in response to electric pulses of the same polarity, in which a series resistance setting unit (10) is configured to set a resistance value of the series current path and a parallel resistance setting unit (30) is configured to set a resistance value of a parallel current path such that the resistance values become resistance values at which a node potential is not larger than a second voltage level in a state where an electric pulse application device (50) is outputting a first electric pulse after the resistance variable element (22) has switched to the high-resistance state, and the node potential is not larger than a first voltage level in the state where the electric pulse application device (50) is outputting a second electric pulse after the resistance variable element (22) has switched to the low-re
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: April 5, 2011
    Assignee: Panasonic Corporation
    Inventors: Yoshikazu Katoh, Kazuhiko Shimakawa, Zhiqiang Wei
  • Patent number: 7916529
    Abstract: A memory architecture that employs one or more semiconductor PIN diodes is provided. The memory employs a substrate that includes a buried bit/word line and a PIN diode. The PIN diode includes a non-intrinsic semiconductor region, a portion of the bit/word line, and an intrinsic semiconductor region positioned between the non-intrinsic region and the portion of the bit/word line.
    Type: Grant
    Filed: February 13, 2009
    Date of Patent: March 29, 2011
    Assignee: Spansion LLC
    Inventors: Wai Lo, Christie Marrian, Tzu-Ning Fang, Sameer Haddad
  • Patent number: 7894237
    Abstract: A multilevel phase change memory cell may have a plurality of intermediate levels between a set and a reset or a crystalline and amorphous states. These intermediate levels between set and reset may be differentiated not only by programming current, but also by different programming pulse widths. As a result, the intermediate states may be positioned, on the programming current versus programming pulse width curve, in regions of common resistance with a relatively large range of programming current.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: February 22, 2011
    Assignee: Intel Corporation
    Inventors: Ilya V. Karpov, Semyon D. Savransky
  • Patent number: 7889537
    Abstract: The present invention provides a method for writing data to a non-volatile memory device having first wirings and second wirings intersecting one another and memory cells arranged at each intersection therebetween, each of the memory cells having a variable resistive element and a rectifying element connected in series. According to the method, the second wirings are charged to a certain voltage not less than a rectifying-element threshold value, prior to a rise in a selected first wiring. Then, a selected first wiring is charged to a voltage required for writing or erasing, after which a selected second wiring is discharged.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: February 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshiaki Edahiro, Kazushige Kanda, Naoya Tokiwa, Takuya Futatsuyama, Koji Hosono, Shigeo Ohshima
  • Patent number: 7888665
    Abstract: An integrated circuit includes a first electrode and a cup-shaped electrode interface coupled to the first electrode. The integrated circuit includes a dielectric spacer at least partially laterally enclosed by the electrode interface and a resistance changing material laterally enclosed by the spacer and contacting the electrode interface. The integrated circuit includes a second electrode coupled to the resistance changing material.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: February 15, 2011
    Assignee: Qimonda AG
    Inventors: Thomas Happ, Jan Boris Philipp
  • Patent number: 7889538
    Abstract: A three-dimensional memory device includes: a plurality of mats laminated therein, each having memory cells arranged in a two-dimensional manner; and access signal lines and data lines to select memory cells in each mat being shared between respective adjacent mats. Laminated mats are divided into three or more groups. When selecting one of these groups, memory cells in some of the remaining groups are biased so that a leakage current flows therethrough, while memory cells in the rest of the remaining groups are biased so that a leakage current does not flow therethrough.
    Type: Grant
    Filed: July 10, 2009
    Date of Patent: February 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Haruki Toda
  • Patent number: 7884345
    Abstract: A phase-change material and a memory unit using the phase-change material are provided. The phase-change material is in a single crystalline state and includes a compound of a metal oxide or nitroxide, wherein the metal is at least one selected from a group consisting of indium, gallium and germanium. The memory unit includes a substrate; at least a first contact electrode formed on the substrate; a dielectric layer disposed on the substrate and formed with an opening for a layer of the phase-change material to be formed therein; and at least a second contact electrode disposed on the dielectric layer. As the phase-change material is in a single crystalline state and of a great discrepancy between high and low resistance states, the memory unit using the phase-changed material can achieve a phase-change characteristic rapidly by pulse voltage and avert any incomplete reset while with a low critical power.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: February 8, 2011
    Assignee: National Taiwan University
    Inventors: Lung-Han Peng, Sung-Li Wang, Meng-Kuei Hsieh, Chien-Yu Chen
  • Patent number: 7881092
    Abstract: An integrated circuit including a resistive memory element and a method of manufacturing the integrated circuit are described. The method of manufacturing the integrated circuit includes depositing a switching layer material and intentionally forming inhomogeneously distributed defects within the switching layer material to increase a number of switching cycles of the resistive memory element. The resistive memory element includes a switching layer that selectively switches between a low resistance state and a high resistance state. The switching layer contains intentionally formed defects that increase the number of switching cycles of the switching layer.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: February 1, 2011
    Assignee: Rising Silicon, Inc.
    Inventor: Klaus Ufert
  • Patent number: 7881095
    Abstract: Apparatus and associated method for asymmetric write current compensation for resistive sense memory (RSM) cells, such as but not limited to spin-torque transfer random access memory (STRAM) or resistive random access memory (RRAM) cells. In accordance with some embodiments, an RSM cell includes an RSM element coupled to a switching device. The switching device has a plurality of terminals. A control circuit compensates for asymmetric write characteristics of the RSM cell by limiting a range of voltage differentials across the terminals so as to be equal to or less than a magnitude of a source voltage applied to the switching device, thereby providing bi-directional write currents of substantially equal magnitude through the RSM element.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: February 1, 2011
    Assignee: Seagate Technology LLC
    Inventors: Yong Lu, Harry Hongyue Liu
  • Patent number: 7881094
    Abstract: Various embodiments of the present invention are generally directed to an apparatus and associated method for generating a reference voltage for a resistive sense memory (RSM) cell, such as an STRAM cell. A dummy reference cell used to generate a reference voltage to sense a resistive state of an adjacent RSM cell. The dummy reference cell comprises a switching device, a resistive sense element (RSE) programmed to a selected resistive state, and a dummy resistor coupled to the RSE. A magnitude of the reference voltage is set in relation to the selected resistive state of the RSE and the resistance of the dummy resistor.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: February 1, 2011
    Assignee: Seagate Technology LLC
    Inventors: Yiran Chen, Hai Li, Harry Hongyue Liu, KangYong Kim, Henry F. Huang
  • Patent number: 7876605
    Abstract: A phase change memory having a memory material layer consisting of a phase change material, and a first and second electrical contact which are located at a distance from one another and via which a switching zone of the memory material layer can be traversed by a current signal, wherein the current signal can be used to induce a reversible phase change between a crystalline phase and an amorphous phase and thus a change in resistance of the phase change material in the switching zone. The invention also relates to a phase change memory assembly, a phase change memory cell, a 2D phase change memory cell array, a 3D phase change memory cell array and an electronic component.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: January 25, 2011
    Assignees: Rheinisch-Westfaelische Technische Hochschle Aachen, Commisssariat a l'Energie Atomique
    Inventors: Peter Haring Bolivar, Bernard Bechevet, Veronique Sousa, Dae-Hwang Kim, Heinrich Kurz, Florian Merget
  • Patent number: 7876608
    Abstract: A method of programming a phase change device includes selecting a desired threshold voltage (Vth) and applying a programming pulse to a phase change material in the phase change device. The applying of the programming pulse includes applying a quantity of energy to the phase change material to drive at least a portion of this material above a melting energy level. A portion of the energy applied to the phase change material is allowed to dissipate below the melting energy level. The shape of the energy dissipation from the phase change material is controlled until the energy applied to the phase change material is less than a quenched energy level, to cause the phase change device to have the desired Vth. A remaining portion of the energy applied to the phase change material is allowed to dissipate to an environmental level.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: January 25, 2011
    Assignee: Macronix International Co., Ltd.
    Inventors: Ming Hsiu Lee, Yi Chou Chen
  • Patent number: 7872901
    Abstract: A memory cell (10) includes a resistive structure (1), and at least two electrodes (2) coupled to the resistive structure (1), wherein: the resistive structure (1) includes hydrogen, and the resistive structure (1) includes a material that exhibits a hydrogen ion mobility value of at least 10?8cm2/Vs.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: January 18, 2011
    Assignee: International Business Machines Corporation
    Inventors: Johannes Georg Bednorz, Siegfried F. Karg, Gerhard Ingmar Meijer
  • Patent number: 7869249
    Abstract: A method and apparatus is disclosed for sensing the resistance state of a Programmable Conductor Random Access Memory (PCRAM) element using complementary PCRAM elements, one holding the resistance state being sensed and the other holding a complementary resistance state. A sense amplifier detects voltages discharging through the high and low resistance elements to determine the resistance state of an element being read.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: January 11, 2011
    Assignee: Micron Technology, Inc.
    Inventors: Glen Hush, Jake Baker
  • Patent number: 7869255
    Abstract: A non-volatile memory device includes a substrate having a recess thereon, a resistant material layer pattern in the recess, a lower electrode on the resistant material layer pattern in the recess, a dielectric layer, and an upper electrode formed on the dielectric layer. The resistant material layer pattern includes a material whose resistance varies according to an applied voltage. The dielectric layer is formed on the substrate, the resistant material layer pattern and the lower electrode. An upper electrode overlaps the resistant material layer pattern and the lower electrode. The applied voltage is applied to access the upper and lower electrodes to vary the resistance of the resistant material layer pattern.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: January 11, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Byung Yong Choi, Choong Ho Lee, Kyu Charn Park
  • Patent number: 7869285
    Abstract: Devices and systems for generating a bias current with a low minimum voltage, for example, are disclosed. One such device includes a first transistor having a source coupled to a voltage supply, a drain coupled to a first node, and a gate coupled to a second node, a second transistor having a source coupled to a reference, and a drain and a gate coupled to the first node, a third transistor having a source coupled to the reference, a drain coupled to a third node, and a gate coupled to the first node, a first resistive element coupled between the voltage supply and the third node, a second resistive element coupled between the voltage supply and the second node, and a fourth transistor having a source coupled to the reference, a drain coupled to the second node, and a gate coupled to the third node.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: January 11, 2011
    Assignee: Micron Technology, Inc
    Inventor: Dong Pan
  • Patent number: 7864602
    Abstract: A non-volatile semiconductor storage device includes: a plurality of memory cells storing information based on a change in resistance value; and a plurality of first and second wirings connected to the plurality of memory cells and activated in reading data from and writing data to a certain one of the memory cells. Each of the memory cells includes: an irreversible storage element storing information based on a change in resistance value associated with breakdown of an insulation film; and a voltage booster circuit receiving an input of a voltage-boost clock performing clock operation in writing data to a certain one of the memory cells and applying a voltage-boosted signal boosted based on the voltage-boost clock to one end of the irreversible storage element.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: January 4, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroshi Ito
  • Patent number: 7864565
    Abstract: A data retention monitor for a memory cell including a voltage source and a voltage comparator. The voltage source is adapted to provide a selectable voltage to the memory cell. The selectable voltage includes a read voltage and a test voltage, with the test voltage being greater than the read voltage. The voltage comparator is adapted to compare a voltage of the memory cell with a reference voltage after the provision of the selectable voltage to the memory cell. The memory cell retains data when the memory cell voltage generated at least in part by the test voltage is substantially equal to the reference voltage.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: January 4, 2011
    Assignee: Infineon Technologies AG
    Inventors: Thomas Nirschl, Jan Otterstedt, Christian Peters, Michael Bollu, Wolf Allers, Michael Sommer
  • Patent number: 7859888
    Abstract: A device having a resistive memory element, a control device, a digit line and a sensing circuit. The sensing circuit is configured to sense a voltage correlative to a resistance state of the resistive memory element. The sensing circuit if further configured to sense the voltage correlative to the resistance state after a waiting period that is less than or equal to the product of a capacitance of a digit line and a total resistance of the control device.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: December 28, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Jun Liu, Glen Hush, Mike Violette, Mark Ingram
  • Patent number: 7859887
    Abstract: A method of programming a nonvolatile memory cell includes applying at least one initialization pulse having a duration of at least 1 ms, followed by applying plural programming pulses having a duration of less than 1 ms. The cell includes a steering element located in series with a storage element, and the storage element includes a carbon material.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: December 28, 2010
    Assignee: SanDisk 3D LLC
    Inventors: Xiying Chen, Tanmay Kumar
  • Patent number: 7859886
    Abstract: A resistance memory element memorizing a high resistance state or a low resistance state in a memory region and switched between the high resistance state and the low resistance state by an application of a voltage includes a resistance memory layer 42 of a resistance memory material, an electrode 38 and an electrode 40 arranged, sandwiching the resistance memory layer 42. The electrode 38 and the electrode 40 are formed on the same surface, whereby the manufacturing process of the resistance memory element can be simplified.
    Type: Grant
    Filed: April 17, 2008
    Date of Patent: December 28, 2010
    Assignee: Fujitsu Limited
    Inventor: Kentaro Kinoshita
  • Patent number: 7859885
    Abstract: A phase change memory device includes a substrate, a plurality of cell arrays stacked above the substrate and each including a matrix layout of a plurality of memory cells, each the memory cell storing therein as data a resistance value determinable by a phase change, a write circuit configured to write a pair cell constituted by two neighboring memory cells within the plurality of cell arrays in such a manner as to write one of the pair cell into a high resistance value state and write the other into a low resistance value state, and a read circuit configured to read complementary resistance value states of the pair cell as a one bit of data.
    Type: Grant
    Filed: January 7, 2008
    Date of Patent: December 28, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Haruki Toda
  • Patent number: 7859883
    Abstract: A memory device includes a plurality of memory cells each including a recordable layer between two metal layers, the recordable layer including a first sub-cell and a second sub-cell. Each memory cell is constructed and designed to change from an as-deposited state to an initialized state upon application of an initialization signal, from the initialized state to a first inscribed state upon application of a first write signal, and from the initialized state to a second inscribed state upon application of a second write signal. The memory cell has a resistor-like current-voltage (I-V) characteristic when in the as-deposited state, a diode-like I-V characteristic when in the initialized state, and resistor-like I-V characteristics when in the first and second inscribed states for voltages within a predetermined range.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: December 28, 2010
    Assignee: Hong Kong Applied Science and Technology Research Institute Co. Ltd.
    Inventors: Geoffrey Wen-Tai Shuy, Hsin-Cheng Lai
  • Patent number: 7852660
    Abstract: An apparatus and method for enhancing read and write sense margin in a memory cell having a resistive sense element (RSE), such as but not limited to a resistive random access memory (RRAM) element or a spin-torque transfer random access memory (STRAM) element. The RSE has a hard programming direction and an easy programming direction. A write current is applied in either the hard programming direction or the easy programming direction to set the RSE to a selected programmed state. A read circuit subsequently passes a read sense current through the cell in the hard programming direction to sense the selected programmed state of the cell.
    Type: Grant
    Filed: April 17, 2009
    Date of Patent: December 14, 2010
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Hai Li, Yiran Chen, Xiaobin Wang, Henry Huang, Haiwen Xi
  • Patent number: 7852657
    Abstract: The present invention relates to a method of programming an array of memory cells such as phase change memory cells. In this method, a selection is made between a first pulse configuration and a second pulse configuration, wherein the first and second pulse configurations are different, and wherein each pulse configuration can write at least two data states to the memory cells of the array.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: December 14, 2010
    Assignee: Qimonda AG
    Inventors: Thomas Happ, Jan Boris Philipp
  • Patent number: 7838862
    Abstract: A phase random access memory including a plurality of access transistors, each access transistor including a drain region and a phase-changeable film shared by the plurality of access transistors. The phase-changeable film is connected to a bitline through a first electrode and connected to each respective drain region through at least one of a plurality of second electrodes.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: November 23, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyung-Rok Oh, Beak-Hyung Cho, Du-Eung Kim, Woo-Yeong Cho
  • Patent number: 7835173
    Abstract: The present disclosure includes resistive memory devices and systems having resistive memory cells, as well as methods for operating the resistive memory cells. One memory device embodiment includes at least one resistive memory element, a programming circuit, and a sensing circuit. For example, the programming circuit can include a switch configured to select one of N programming currents for programming the at least one resistive memory element, where each of the N programming currents has a unique combination of current direction and magnitude, with N corresponding to the number of resistance states of the at least one memory element. In one or more embodiments, the sensing circuit can be arranged for sensing of the N resistance states.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: November 16, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Yantao Ma, Jun Liu
  • Patent number: 7834340
    Abstract: Phase change memory devices are provided including a selection element electrically connected to a phase change material pattern. The selection element includes a metallic conductor and a semiconductor that are in contact with each other. A depletion region in contact with a metallic pattern is generated in the semiconductor in an equilibrium state. The depletion region includes a high barrier region having an electric potential barrier higher than an interface electric potential barrier and a low barrier region having an electric potential barrier lower than the interface electric potential barrier. Related methods are also provided.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: November 16, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Nam-Bin Kim
  • Patent number: 7835174
    Abstract: The present invention provides a method of reading data from a non-volatile memory device including word lines and bit lines that intersect each other and electrically rewritable memory cells that are arranged at intersections of the word lines and the bit lines and that respectively have variable resistive elements nonvolatily storing a resistances as data. The method includes: precharging a selected word line and unselected word lines to a first word line voltage and a selected bit line and unselected bit lines to a first bit line voltage; and reading data from a memory cell connected to the selected word line and the selected bit line by changing the voltage of the selected word line from the first word line voltage to a second word line voltage and changing the voltage of the selected bit line from the first bit line voltage to a second bit line voltage after the precharging.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: November 16, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Naoya Tokiwa
  • Patent number: 7835177
    Abstract: A phase change memory (PCM) cell fabricated by etching a tapered structure into a phase change layer, and planarizing a dielectric layer on the phase change layer until a tip of the tapered structure is exposed for contacting a heating electrode. Therefore, the area of the exposed tip of the phase change layer is controlled to be of an extremely small size, the contact area between the phase change layer and the heating electrode is reduced, thereby lowering the operation current.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: November 16, 2010
    Assignee: Industrial Technology Research Institute
    Inventors: Hong-Hui Hsu, Chien-Min Lee, Wen-Han Wang, Min-Hung Lee, Te-Sheng Chao, Yen Chuo, Yi-Chan Chen, Wei-Su Chen
  • Patent number: 7830700
    Abstract: Various embodiments of the present invention are generally directed to a method and apparatus for carrying out a partial block update operation upon a resistive sense memory (RSM) array, such as formed from STRAM or RRAM cells. The RSM array is arranged into multi-cell blocks (sectors), each block having a physical block address (PBA). A first set of user data is written to a selected block at a first PBA. A partial block update operation is performed by writing a second set of user data to a second block at a second PBA, the second set of user data updating a portion of the first set of user data in the first PBA. The first and second blocks are thereafter read to retrieve the second set of user data and a remaining portion of the first set of user data.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: November 9, 2010
    Assignee: Seagate Technology LLC
    Inventors: Yiran Chen, Daniel S. Reed, Yong Lu, Harry Hongyue Liu, Hai Li
  • Patent number: 7821803
    Abstract: A memory module having a start-type topology and a method of fabricating the same are provided. The memory module includes a substrate. Memory devices are mounted on the substrate in at least two rows and at least two columns. A star-type topology is disposed to be electrically connected to the memory devices. One or more pairs of adjacent ones of the memory devices have a point-symmetric structure.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: October 26, 2010
    Assignee: Samsung Electronics, Co., Ltd.
    Inventors: Do-Hyung Kim, Byoung-Ha Oh, Young-Jun Park, Yong-Ho Ko
  • Patent number: 7817475
    Abstract: Fixed-voltage programming pulses are employed to program a phase change memory cell. A burst of incrementally widening fixed-voltage programming pulses may be employed to program a phase change memory to a target threshold voltage.
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: October 19, 2010
    Assignee: Ovonyx, Inc.
    Inventor: Tyler Lowrey
  • Patent number: 7813158
    Abstract: A memory device includes memory cells each having a recordable layer between two metal layers, each memory cell being constructed and designed to change from a first state to a second state upon application of an initialization signal, and change from the second state to a third state upon application of a write signal. For a voltage within a specified range that is applied across the two metal layers, the memory cell has a lower resistance in the first state than in the second state, and has a higher resistance in the second state than in the third state.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: October 12, 2010
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Geoffrey Wen-Tai Shuy, Hsin-Cheng Lai
  • Patent number: 7807995
    Abstract: A nonvolatile semiconductor memory apparatus 25 comprises a semiconductor substrate 11, a lower-layer wire 12 formed on the semiconductor substrate 11, an upper-layer wire 20 formed above the lower-layer wire 12 to cross the lower-layer wire 12, an interlayer insulating film 13 provided between the lower-layer wire 12 and the upper-layer wire 20, and a resistance variable layer 15 which is embedded in a contact hole 14 formed in the interlayer insulating film 13 and is electrically connected to the lower-layer wire 12 and the upper-layer wire 20. The upper-layer wire 20 includes at least two layers which are a lowermost layer 21 made of an electrically-conductive material having a hydrogen barrier property and an electric conductor layer 22 having a specific resistance which is lower than a specific resistance of the lowermost layer 21.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: October 5, 2010
    Assignee: Panasonic Corporation
    Inventors: Takumi Mikawa, Takesi Takagi
  • Patent number: 7808810
    Abstract: A nonvolatile memory cell includes a layer of a resistivity-switching metal oxide or nitride compound, the metal oxide or nitride compound including one metal, and a dielectric rupture antifuse formed in series. The dielectric rupture antifuse may be either in its initial, non-conductive state or a ruptured, conductive state. The resistivity-switching metal oxide or nitride layer can be in a higher- or lower-resistivity state. By using both the state of the resistivity-switching layer and the antifuse to store data, more than two bits can be stored per memory cell.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: October 5, 2010
    Assignee: Sandisk 3D LLC
    Inventor: S. Brad Herner
  • Patent number: 7796416
    Abstract: Provided is a variable resistance element capable of performing a stable resistance switching operation and having a favorable resistance value retention characteristics, comprising a variable resistor 2 sandwiched between a upper electrode 1 and lower electrode 3 and formed of titanium oxide or titanium oxynitride having a crystal grain diameter of 30 nm or less. When the variable resistance 2 is formed under the substrate temperature of 150° C. to 500° C., an anatase-type crystal having a crystal grain diameter of 30 nm or less is formed. Since the crystalline state of the variable resistor changes by applying a voltage pulse and the resistance value changes, no forming process is required. Moreover, it is possible to perform a stable resistance switching operation and obtain an excellent effect that the resistance fluctuation is small even if the switching is repeated, or the variable resistance element is stored for a long time under a high temperature.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: September 14, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kazuya Ishihara, Yasunari Hosoi, Shinji Kobayashi
  • Patent number: 7791923
    Abstract: A multi-bit memory cell stores information corresponding to a high resistive state and multiple other resistive states lower than the high resistive state. A resistance of a memory element within the multi-bit memory cell switches from the high resistive state to one of the other multiple resistive states by applying a corresponding current to the memory element.
    Type: Grant
    Filed: January 3, 2007
    Date of Patent: September 7, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: In-Gyu Baek, Dong-Chul Kim, Jang-Eun Lee, Myoung-Jae Lee, Sun-Ae Seo, Hyeong-Jun Kim, Seung-Eon Ahn, Eun-Kyung Yim
  • Patent number: 7791933
    Abstract: A system of writing data to a phase change random access memory (PCRAM) on an integrated circuit (IC), and a design structure including the IC embodied in a machine readable medium are disclosed. The system includes an array of phase change elements with a plurality of devices providing independent control of a row access and a column access to the PCRAM. A column line (bit line) is pre-charged to a single predetermined level prior to enabling current flow to a corresponding selected phase change element. A current flow in the phase change element with a row (word line) is initiated once the column (bit line) has been pre-charged, to write data to the PCRAM cell. The current flow is terminated in the phase change element by closing the column line (bit line) preferably by quenching.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: September 7, 2010
    Assignee: International Business Machines Corporation
    Inventors: Mark Lamorey, Thomas Happ
  • Patent number: 7787280
    Abstract: An electric element includes a first terminal (1), a second terminal (3), and a variable-resistance film (2). The variable-resistance film (2) is connected between the first terminal (1) and the second terminal (3). The variable-resistance film (2) includes Fe3O4 crystal phase and Fe2O3 crystal phase.
    Type: Grant
    Filed: April 4, 2006
    Date of Patent: August 31, 2010
    Assignee: Panasonic Corporation
    Inventors: Satoru Mitani, Koichi Osano, Shunsaku Muraoka, Kumio Nago
  • Patent number: 7787278
    Abstract: Provided is a resistance variable memory device and a method for operating same. The resistance variable memory device has a phase change material between a top electrode and a bottom electrode. In the method for operating a resistance variable memory, the write current is applied in a direction from the top electrode to the bottom electrode, and the read current is applied in a direction from the bottom electrode to the top electrode. The phase change material is programmed by applying the write current, and a resistance drift of the phase change material is restrained by applying the read current.
    Type: Grant
    Filed: August 22, 2008
    Date of Patent: August 31, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jun-Soo Bae, Hideki Horii, Mi-Lim Park
  • Patent number: 7778066
    Abstract: Provided is a method of programming a resistance variable memory device. The resistance variable memory device includes a memory cell having multi states and a write driver outputting a program pulse for programming the memory cell into one of the multi states. The method of programming the resistance variable memory device includes applying a first program pulse to the resistance variable memory device and applying a second program pulse to a memory cell when the memory cell is programmed into an intermediate state. When the first program pulse is a reset pulse, the reset pulse is an over program pulse, that is, an over reset pulse. Therefore, the resistance variable memory device can secure a sufficient read margin as well as improve a resistance drift margin.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: August 17, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hideki Horii, Jun-Soo Bae
  • Patent number: 7778079
    Abstract: In a memory device and in a method of programming the same, a memory device comprises: a plurality of memory cells, each memory cell comprising a resistance-changeable material that has an initial resistance that is determined in response to an applied programming current in a programming operation; and a modification circuit that modifies the resistance of the memory cell following a programming operation of the memory cell to vary the resistance of the memory cell from the initial resistance to a second resistance by applying a saturation current in a saturation operation. Each memory cell is connected to a conduction line of the memory device that is used to apply the programming current to program the resistance of the corresponding memory cell in the programming operation, that is used to apply the saturation current to the corresponding memory cell in the saturation operation and that is used to apply a read current to read the resistance of the corresponding memory cell in a subsequent read operation.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: August 17, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chang-Wook Jeong, Dae-Hwan Kang, Hyeong-Jun Kim, Jae-Min Shin, Seung-Pil Ko
  • Patent number: 7773409
    Abstract: A writing method for a phase change memory is disclosed. The writing method inputs a first writing pulse signal to a phase change memory to heat the phase change memory to above a first temperature and inputting a second writing pulse signal to the phase change memory to keep the phase change memory at a second temperature.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: August 10, 2010
    Assignee: Industrial Technology Research Institute
    Inventors: Ming-Jung Chen, Te-Sheng Chao, Philip H. Yeh
  • Patent number: 7768812
    Abstract: Embodiments disclosed include memory cell operating methods, memory cell programming methods, memory cell reading methods, memory cells, and memory devices. In one embodiment, a memory cell includes a wordline, a first bitline, a second bitline, and a memory element. The memory element is electrically connected to the wordline and selectively electrically connected to the first bitline and the second bitline. The memory element stores information via a resistive state of the memory element. The memory cell is configured to convey the resistive state of the memory element via either a first current flowing from the first bitline through the memory element to the wordline or a second current flowing from the wordline through the memory element to the second bitline.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: August 3, 2010
    Assignee: Micron Technology, Inc.
    Inventor: Jun Liu
  • Patent number: 7768810
    Abstract: In an integrated circuit, a radiation tolerant static random access memory device comprising a first inverter having an input and an output, a second inverter having an input and an output. A first resistor is coupled between the output of the first inverter and the input of the second inverter. A second resistor is coupled between the output of the second inverter and the input of the first inverter. A first write transistor is coupled to the output of the first inverter and has a gate coupled to a source of a first set of write-control signals and a second write transistor is coupled to the output of the second inverter and has a gate coupled to said source of a second set of write-control signals. Finally, a pass transistor has a gate coupled to the output of on of the first and second inverters.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: August 3, 2010
    Assignee: Actel Corporation
    Inventor: John McCollum
  • Patent number: 7764532
    Abstract: A high speed sensing scheme for a non-volatile memory array is disclosed. The memory array includes non volatile memory cells arranged in a complementary bitline configuration includes precharge circuits for precharging the bitlines to a first voltage level such as VSS, a reference circuits for applying a reference charge on the reference bitlines of the complementary bitline pairs, and bitline sense amplifiers for sensing a voltage differential between the complementary bitline pairs. A voltage on the data bitline being changed when a programmed non-volatile memory cell connected to an activated wordline couples the wordline voltage to the data bitline.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: July 27, 2010
    Assignee: Sidense Corp.
    Inventors: Wlodek Kurjanowicz, Steven Smith
  • Patent number: RE41838
    Abstract: An output buffer circuit of the present invention includes a plurality of unit circuits in each of which a pull-up transistor controlled by a first input signal is connected between a high-potential power supply and common node, and a pull-down transistor controlled by a second input signal is connected between the common node and a low-potential power supply, an output terminal connected to a common connecting point of the common nodes of the plurality of unit circuits, and first resistors formed respectively between the common nodes of the plurality of unit circuits and the common connecting point.
    Type: Grant
    Filed: July 25, 2008
    Date of Patent: October 19, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Go Iwasaki
  • Patent number: RE42144
    Abstract: The present invention relates to a non-volatile memory comprising a memory array comprising functional memory cells and non-functional memory cells linked to at least one non-functional word line. A word line address decoder comprises a special decoding section linked to the non-functional word line, for selecting the non-functional word line when a functional word line is read-selected, such that non-functional memory cells are selected simultaneously with the functional memory cells, and distort the reading of the functional memory cells. Application particularly to integrated circuits for smart cards.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: February 15, 2011
    Assignee: STMicroelectronics S.A.
    Inventor: Mathieu Lisart