Diodes Patents (Class 365/175)
  • Patent number: 6894305
    Abstract: Phase change memory devices include a phase-change memory layer on a semiconductor substrate. The phase-change memory layer has a major axis that is substantially parallel to a major axis of the semiconductor substrate and has a first surface and a second surface opposite the first surface that are substantially parallel to the major axis of the phase-change memory layer. A first electrode is provided on the semiconductor substrate that is electrically connected to the first surface of the phase-change memory layer in a first contact region of the phase-change memory layer. A second electrode is provided on the semiconductor substrate that is electrically connected to the phase-change memory layer in a second contact region of the phase-change memory layer. The second contact region is space apart from the first contact region.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: May 17, 2005
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ji-hye Yi, Horii Hideki, Yong-ho Ha
  • Patent number: 6891744
    Abstract: Configurable electronic circuits comprise arrays of cross-points of one layer of metal/semiconductive nanoscale lines crossed by a second layer of metal/semiconductive nanoscale lines, with a configurable layer between the lines. Methods are provided for altering the thickness and/or resistance of the configurable layer by oxidation or reduction methods, employing a solid material as the configurable layer. Specifically a method is provided for configuring nanoscale devices in a crossbar array of configurable devices comprising arrays of cross-points of a first layer of nanoscale lines comprising a first metal or a first semiconductor material crossed by a second layer of nanoscale lines comprising a second metal or a second semiconductor material.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: May 10, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Yong Chen, R. Stanley Williams
  • Patent number: 6885573
    Abstract: A data storage device is disclosed that has a plurality of word lines, a plurality of bit lines, and a resistive crosspoint array of memory cells. Each memory cell is connected to a bit line and connected to an isolation diode that further connects to a respective word line. The isolation diode provides a unidirectional conductive path from the bit line to the word line. Each word line provides a common metal-semiconductor contact with each diode sharing the word line such that each diode has a separate metal contact located between the semiconductor portion of the common metal-semiconductor contact and its respective memory cell.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: April 26, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Manish Sharma, Lung T. Tran
  • Patent number: 6873544
    Abstract: A data storage device that includes an array of resistive memory cells. The resistive memory cells may include a magnetic tunnel junction (MTJ) and a thin-film diode. The device may include a circuit that is electrically connected to the array and that is also capable of monitoring a signal current flowing through a selected memory cell. Once the signal current has been monitored, the circuit is capable of comparing the signal current to an average reference current in order to determine which of a first resistance state and a second resistance state the selected memory cell is in. Also, a method for operating the data storage device.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: March 29, 2005
    Assignee: Hewlett-Packard Company, L.P.
    Inventors: Frederick A. Perner, Lung T. Tran, Kenneth J. Eldredge
  • Patent number: 6853022
    Abstract: A semiconductor memory device having as its main storage portion a capacitor storing charges as binary information and an access transistor controlling input/output of the charges to/from the capacitor, and eliminating the need for refresh, is obtained. The semiconductor memory device includes a capacitor with a storage node located above a semiconductor substrate and holding the charges corresponding to a logical level of stored binary information, an access transistor located on the semiconductor substrate surface and controlling input/output of the charges accumulated in the capacitor, and a latch circuit located on the semiconductor substrate and maintaining a potential of the capacitor storage node. At least one of circuit elements constituting the latch circuit is located above the access transistor.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: February 8, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Tsuyoshi Koga, Yoshiyuki Ishigaki, Motoi Ashida, Yukio Maki, Yasuhiro Fujii, Tomohiro Hosokawa, Takashi Terada, Makoto Dei, Yasuichi Masuda
  • Patent number: 6829169
    Abstract: An electrically erasable and programmable memory includes an array of memory cells, and a distribution line linked to a receiving terminal of an external supply voltage and to a booster circuit. The distribution line provides an internal supply voltage. The distribution line is also linked to the receiving terminal through a diode or a diode circuit simulating operation of a diode. The memory includes a regulator for triggering the booster circuit when the internal supply voltage becomes lower than a threshold so as to maintain the internal supply voltage close to the threshold when the external supply voltage is too low, at least during the reading of memory cells. The diode or the diode circuit is blocked when the external supply voltage is too low.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: December 7, 2004
    Assignee: STMicroelectronics SA
    Inventors: Filipe Ganivet, Francesco La Rosa, Thierry Giovinazzi
  • Patent number: 6816404
    Abstract: The phase-change nonvolatile memory array is formed by a plurality of memory cells extending in a first and in a second direction orthogonal to each other. A plurality of column-selection lines extend parallel to the first direction. A plurality of word-selection lines extend parallel to the second direction. Each memory cell includes a PCM storage element and a selection transistor. A first terminal of the selection transistor is connected to a first terminal of the PCM storage element, and the control terminal of the selection transistor is connected to a respective word-selection line. A second terminal of the PCM storage element is connected to a respective column-selection line, and a second terminal of the selection transistor is connected to a reference-potential region while reading and programming the memory cells.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: November 9, 2004
    Assignees: STMicroelectronics S.r.l., OVONYX, Inc.
    Inventors: Osama Khouri, Ferdinando Bedeschi, Giorgio Bosisio, Fabio Pellizzer
  • Patent number: 6816410
    Abstract: A three-dimensional memory array includes a plurality of rail-stacks on each of several levels forming alternating levels of X-lines and Y-lines for the array. Memory cells are formed at the intersection of each X-line and Y-line. The memory cells of each memory plane are all oriented in the same direction relative to the substrate, forming a serial chain diode stack. In certain embodiments, row and column circuits for the array are arranged to interchange function depending upon the directionality of memory cells in the selected memory plane. High-voltage drivers for the X-lines and Y-lines are each capable of passing a write current in either direction depending on the direction of the selected memory cell. A preferred bias arrangement reverse biases only unselected memory cells within the selected memory plane, totaling approximately N2 memory cells, rather than approximately 3N2 memory cells as with prior arrays.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: November 9, 2004
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Bendik Kleveland, Roy E. Scheuerlein
  • Patent number: 6813182
    Abstract: A donor/acceptor-organic-junction sheet employed within an electronic memory array of a cross-point diode memory. The donor/acceptor-organic-junction sheet is anistropic with respect to flow of electrical current and is physically unstable above a threshold current. Thus, the volume of the donor/acceptor-organic-junction sheet between a row line and column line at a two-dimensional memory array grid point serves both as the diode component and as the fuse component of a diode-and-fuse memory element and is electrically insulated from similar volumes of the donor/acceptor-organic-junction sheet between neighboring grid point intersections.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: November 2, 2004
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Craig M Perlov, Stephen Forrest
  • Patent number: 6781907
    Abstract: A T-RAM memory cell includes a temperature compensation device to adjust the gate-to-source voltage of an access transistor for the memory cell as a function of temperature so that the sub-threshold current of the transistor is insensitive to temperature variations. As a result, the sub-threshold current can be maintained slightly above the holding current of a thyristor used in the memory cell despite substantial temperature variations. In one embodiment, the temperature compensation device includes a current source directing a fixed current through a diode-connected transistor of the type used as the memory cell access transistor. Temperature induced changes in a reference voltage generated at the junction between the current source and the transistor therefore match the temperature induced changed in the sub-threshold current of the access transistor.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: August 24, 2004
    Assignee: Micron Technology, Inc.
    Inventor: Ken W. Marr
  • Patent number: 6765821
    Abstract: There are provided at least one wire, a magnetoresistive effect element having a storage layer whose magnetization direction varies according to a current magnetic field generated by causing a current to flow in the wire, and first yokes provided so as to be spaced from at least one pair of opposed side faces of the magnetoresistive effect element to form a magnetic circuit in cooperation with the magnetoresistive effect element when a current is caused to flow in the wire. Each of the first yokes has at least two soft magnetic layers which are stacked via a non-magnetic layer.
    Type: Grant
    Filed: September 16, 2003
    Date of Patent: July 20, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Tomomasa Ueda, Tatsuya Kishi, Minoru Amano
  • Patent number: 6765303
    Abstract: A SRAM cell includes a single FinFET and two resonant tunnel diodes. The FinFet has multiple channel regions formed from separate fins. The resonant tunnel diodes may be formed from FinFET type fins. In particular, the resonant diodes may includes a thin, undoped silicon region surrounded by a dielectric. The SRAM cell is small and provides fast read/write access times.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: July 20, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Zoran Krivokapic, Judy Xilin An, Matthew S. Buynoski
  • Patent number: 6757188
    Abstract: A data storage device that includes an array of resistive memory cells. The resistive memory cells may include a magnetic tunnel junction (MTJ) and a thin-film diode. The device may include a circuit that is electrically connected to the array and that is also capable of monitoring a signal current flowing through a selected memory cell. Once the signal current has been monitored, the circuit is capable of comparing the signal current to an average reference current in order to determine which of a first resistance state and a second resistance state the selected memory cell is in. Also, a method for operating the data storage device.
    Type: Grant
    Filed: May 22, 2002
    Date of Patent: June 29, 2004
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Frederick A. Perner, Lung T. Tran, Kenneth J. Eldredge
  • Patent number: 6754102
    Abstract: A three-dimensional memory array includes a plurality of rail-stacks on each of several levels forming alternating levels of X-lines and Y-lines for the array. Memory cells are formed at the intersection of each X-line and Y-line. The memory cells of each memory plane are all oriented in the same direction relative to the substrate, forming a serial chain diode stack. In certain embodiments, row and column circuits for the array are arranged to interchange function depending upon the directionality of memory cells in the selected memory plane. High-voltage drivers for the X-lines and Y-lines are each capable of passing a write current in either direction depending on the direction of the selected memory cell. A preferred bias arrangement reverse biases only unselected memory cells within the selected memory plane, totaling approximately N2 memory cells, rather than approximately 3N2 memory cells as with prior arrays.
    Type: Grant
    Filed: September 24, 2002
    Date of Patent: June 22, 2004
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Bendik Kleveland, Roy E. Scheuerlein
  • Patent number: 6747301
    Abstract: A tunneling barrier for a spin dependent tunneling (SDT) device is disclosed that includes a plurality of ferromagnetic atoms disposed in a substantially homogenous layer. The presence of such atoms in the tunneling barrier is believed to increase a magnetoresistance or &Dgr;R/R response, improving the signal and the signal to noise ratio. Such an increase &Dgr;R/R response also offers the possibility of decreasing an area of the tunnel barrier layer. Decreasing the area of the tunnel barrier layer can afford improvements in resolution of devices such as MR sensors and increased density of devices such as of MRAM cells.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: June 8, 2004
    Assignee: Western Digital (Fremont), Inc.
    Inventors: Hugh Craig Hiner, Kyusik Sin, Shin Funada, Xizeng Shi, Hua-Ching Tong
  • Patent number: 6744681
    Abstract: A solid state memory device is fabricated by forming a level of the device; identifying defective areas in the level; and programming address logic of the level to avoid the defective areas in the level.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: June 1, 2004
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Josh N. Hogan
  • Patent number: 6731535
    Abstract: A nonvolatile semiconductor memory device includes a silicon substrate, bit lines, word lines, and memory cells. The bit line is positioned above the main surface of the silicon substrate and the word line is provided to intersect the bit line. The memory cell is positioned at a region where the bit line and the word line intersect and has one end electrically connected to the bit line and the other end electrically connected to the word line. The memory cell includes a TMR element and an access diode electrically connected in series. The access diode includes an n-type silicon layer and a p-type silicon layer recrystallized by melting-recrystallization and has a pn junction at the interface between the n-type silicon layer and the p-type silicon layer. As a result, a nonvolatile semiconductor memory device reduced in size and having high performance can be manufactured inexpensively.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: May 4, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Tsukasa Ooishi, Shuichi Ueno, Shigehiro Kuge
  • Patent number: 6707712
    Abstract: A cell in a structural phase-change memory is programmed by raising cell voltage and cell current to programming threshold levels, and then lowering these to quiescent levels below their programming levels. A precharge pulse is then applied which raises the bitline voltage of the selected cell and does not raise the cell voltage and cell current to their programming levels. Then, the cell current is raised to a read level which is below the programming threshold level, and the bitline voltage is compared to a reference voltage while the cell current is at the read level.
    Type: Grant
    Filed: June 10, 2003
    Date of Patent: March 16, 2004
    Assignee: Intel Corporation
    Inventor: Tyler A. Lowery
  • Patent number: 6687149
    Abstract: In an optical memory device, an electroluminescent matrix has a plurality of individually electrically addressable electroluminescent cells, each having a stack of memory cells. The electroluminescent cells are addressable by applying a biased voltage through a grid of light-transparent electrodes.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: February 3, 2004
    Assignee: OptaByte, Inc.
    Inventors: Boris Chernobrod, Jacob Malkin, Vladimir Schwartz
  • Publication number: 20030227792
    Abstract: A T-RAM memory cell includes a temperature compensation device to adjust the gate-to-source voltage of an access transistor for the memory cell as a function of temperature so that the sub-threshold current of the transistor is insensitive to temperature variations. As a result, the sub-threshold current can be maintained slightly above the holding current of a thyristor used in the memory cell despite substantial temperature variations. In one embodiment, the temperature compensation device includes a current source directing a fixed current through a diode-connected transistor of the type used as the memory cell access transistor. Temperature induced changes in a reference voltage generated at the junction between the current source and the transistor therefore match the temperature induced changed in the sub-threshold current of the access transistor.
    Type: Application
    Filed: June 6, 2002
    Publication date: December 11, 2003
    Inventor: Ken W. Marr
  • Patent number: 6661704
    Abstract: A method of and apparatus for connecting the sense current line in a cross-point memory array greatly reduces the effect of reverse leakage from unaddressed row or column lines. Separate sense line segments are coupled to separate stripes of row or column lines. Each sense line segment is connected to a sense diode, and each sense diode is connected to a sense bus. Each sense diode provides the current path for sensing on a selected row or column line, while allowing the leakage of only one diode per sense line segment for the unaddressed row or column lines. This arrangement results in wider margins for sensing the state of data cells in a cross-point memory array and simpler circuitry design for the memory array.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: December 9, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: James R. Eaton, Jr.
  • Publication number: 20030223270
    Abstract: A donor/acceptor-organic-junction sheet employed within an electronic memory array of a cross-point diode memory. The donor/acceptor-organic-junction sheet is anistropic with respect to flow of electrical current and is physically unstable above a threshold current. Thus, the volume of the donor/acceptor-organic-junction sheet between a row line and column line at a two-dimensional memory array grid point serves both as the diode component and as the fuse component of a diode-and-fuse memory element and is electrically insulated from similar volumes of the donor/acceptor-organic-junction sheet between neighboring grid point intersections.
    Type: Application
    Filed: May 31, 2002
    Publication date: December 4, 2003
    Inventors: Craig M. Perlov, Stephen Forrest
  • Publication number: 20030210568
    Abstract: An electrically addressable data storage unit has a matrix of rows and columns of data storage arrays on a single substrate. Each array is a matrix of coplanar data storage diode cells connected by row lines and column lines for recording, addressing and reading of data. The address lines and power lines of the plurality of arrays are connected to the arrays so that only the data storage diode cells in the array of a selected data storage cell are enabled, thereby eliminating undesirable power dissipation in all other arrays of the data storage unit.
    Type: Application
    Filed: May 13, 2002
    Publication date: November 13, 2003
    Inventors: James R. Eaton, Michael C. Fischer
  • Patent number: 6646912
    Abstract: A data storage device is disclosed that comprises a cross-point memory array formed on a dielectric substrate material. The cross-point memory array comprises first and second sets of transverse electrodes separated by a storage layer including at least one semiconductor layer. The storage layer forms a non-volatile memory element at each crossing point of electrodes from the first and second sets. Each memory element can be switched between low and high impedance states, representing respective binary data states, by application of a write signal in the form of a predetermined current density through the memory element. Each memory element includes a diode junction formed in the storage layer, at least whilst in the low impedance state. A plurality of the data storage devices can be stacked and laminated into a memory module providing inexpensive high capacity data storage.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: November 11, 2003
    Assignee: Hewlett-Packard Development Company, LP.
    Inventors: Terril N. Hurst, Craig Perlov, Carol Wilson, Carl Taussig
  • Publication number: 20030198091
    Abstract: A semiconductor device includes a switching element (ex. a Schottky barrier diode) which control transmission/cutoff of a signal transmitted between two portions of a transmission line. An anode electrode of the switching element is interposed between the two portions of the transmission line while the longitudinal direction of the anode electrode accords with the longitudinal direction of the transmission line. A cathode electrode of the switching element is disposed on at least one of the widthwise sides of the anode electrode, and is connected to the ground.
    Type: Application
    Filed: October 16, 2002
    Publication date: October 23, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshihiro Tsukahara
  • Patent number: 6631085
    Abstract: A three-dimensional memory array includes a plurality of rail-stacks on each of several levels forming alternating levels of X-lines and Y-lines for the array. Memory cells are formed at the intersection of each X-line and Y-line. The memory cells of each memory plane are all oriented in the same direction relative to the substrate, forming a serial chain diode stack. In certain embodiments, row and column circuits for the array are arranged to interchange function depending upon the directionality of memory cells in the selected memory plane. High-voltage drivers for the X-lines and Y-lines are each capable of passing a write current in either direction depending on the direction of the selected memory cell. A preferred bias arrangement reverse biases only unselected memory cells within the selected memory plane, totaling approximately N2 memory cells, rather than approximately 3N2 memory cells as with prior arrays.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: October 7, 2003
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Bendik Kleveland, Roy E. Scheuerlein, N. Johan Knall, Mark G. Johnson, Thomas H. Lee
  • Patent number: 6618304
    Abstract: Embodiments of the present invention provide memory modules that mitigate the problems associated with using address pins on memory modules to supply super voltages to memory devices on the memory modules. In one embodiment, the memory module has a memory device that has a test pin. A pin of the memory module is connected to the test pin. The pin of the memory module connects the test pin to one of ground, a power source, or an open circuit when the memory module is inserted in a socket for operation. The pin of the memory module can be used to selectively supply a test voltage to the test pin when the memory module is not connected for operation.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: September 9, 2003
    Assignee: Micron Technology, Inc.
    Inventor: Kevin Duesman
  • Patent number: 6599796
    Abstract: A cross point memory array is fabricated on a substrate with a plurality of memory cells, each memory cell including a diode and an anti-fuse in series. First and second conducting materials are disposed in separate strips on the substrate to form a plurality of first and second orthogonal electrodes with cross points. A plurality of semiconductor layers are disposed between the first and second electrodes to form a plurality of diodes between the cross points of the first and second electrodes. A passivation layer is disposed between the first electrodes and the diodes to form a plurality of anti-fuses adjacent to the diodes at the cross points of first and second electrodes. Portions of the diode layers are removed between the electrode cross points to form the plurality of memory cells with rows of trenches between adjacent memory cells to provide a barrier against crosstalk between adjacent memory cells. The trenches extend substantially to the depth of the n-doped layer in each diode.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: July 29, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Ping Mei, Carl P. Taussig, Patricia A. Beck
  • Patent number: 6590807
    Abstract: A cell in a structural phase-change memory is programmed by raising cell voltage and cell current to programming threshold levels, and then lowering these to quiescent levels below their programming levels. A precharge pulse is then applied which raises the bitline voltage of the selected cell and does not raise the cell voltage and cell current to their programming levels. Then, the cell current is raised to a read level which is below the programming threshold level, and the bitline voltage is compared to a reference voltage while the cell current is at the read level.
    Type: Grant
    Filed: August 2, 2001
    Date of Patent: July 8, 2003
    Assignee: Intel Corporation
    Inventor: Tyler A. Lowrey
  • Patent number: 6590800
    Abstract: A high speed, low power Static Random Access Memory (SRAM) Array, which includes a 4T cell with two integrated Schottky Barrier Diodes (SBD) is disclosed. In a preferred embodiment, the cell bulk area and speed advantage is 30%, and ac power saving is 75% compared with the 6T CFET cell. The physical construct of the 4T cell saves capacitance in all critical nodes intra or inter cell wise, eliminates pass transistors, reduces the well noises. Typical embodiment uses a 0.15-um-rule based layout, and 1.5V supports operation at 5 ns cycles. SBD are used extensively with CFET to form a CMOS version of the Diode Transistor Logic circuitry. Generic control functions can be implemented including NAND gates, level shifting, decoding, voltage generator, ESD and latch-up protection, leakage control, and dynamic VT setting while in operation. Product applications include DRAM, SRAM, PLD, DRAM, CAM, Flash, Computing, Networking, and Communication devices as standalone system component or embedded into any ASIC.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: July 8, 2003
    Inventor: Augustine Wei-Chun Chang
  • Publication number: 20030123284
    Abstract: Briefly, in accordance with an embodiment of the invention, a method and an apparatus to read a phase change memory is provided, wherein the method includes zero biasing unselected memory cells during reading of a selected memory cell.
    Type: Application
    Filed: December 28, 2001
    Publication date: July 3, 2003
    Inventors: Tyler Lowrey, Daniel Xu
  • Publication number: 20030107917
    Abstract: A method and apparatus of connecting the sense current lines in a cross-point memory array which greatly reduces the effect of reverse leakage from unaddressed row or column lines. Separate sense line segments are coupled to separate stripes of row or column lines. Each sense line segment is connected to a sense diode, and each sense diode is connected to a sense bus. Each sense diode provides the current path for sensing on a selected row or column line, while allowing the leakage of only one diode per sense line segment for the unaddressed row or column lines. This arrangement results in wider margins for sensing the state of data cells in a cross-point memory array and simpler circuitry design for the memory array.
    Type: Application
    Filed: December 10, 2001
    Publication date: June 12, 2003
    Inventor: James R. Eaton
  • Patent number: 6567296
    Abstract: A memory device including a plurality of memory cells, a plurality of insulated first regions of a first type of conductivity formed in a chip of semiconductor material, at least one second region of a second type of conductivity formed in each first region, a junction between each second region and the corresponding first region defining a unidirectional conduction access element for selecting a corresponding memory cell connected to the second region when forward biased, and at least one contact for contacting each first region; a plurality of access elements are formed in each first region, the access elements being grouped into at least one sub-set consisting of a plurality of adjacent access elements without interposition of any contact, and the memory device further includes means for forward biasing the access elements of each sub-set simultaneously.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: May 20, 2003
    Assignees: STMicroelectronics S.r.l., Ovonyx, Inc.
    Inventors: Giulio Casagrande, Tyler Lowrey, Roberto Bez, Guy Wicker, Edward Spall, Stephen Hudgens, Wolodymyr Czubatyj
  • Patent number: 6567295
    Abstract: A memory circuit includes a cross-point memory array having first and second sets of transverse electrodes with respective memory elements formed at the crossing-points of the first and second set electrodes. Each of the memory elements is formed to include, in at least one of its binary states, a diode element. The memory circuit also includes an addressing circuit coupled to the memory array. The addressing circuit has a first set of address lines with first diode connections between the first set address lines and the first set memory array electrodes, with the first diode connections coupling each memory array electrode in the first set to a respective unique subset of the first set address lines.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: May 20, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Carl Taussig, Richard Elder
  • Patent number: 6567301
    Abstract: A one-time programmable unit memory cell includes a vertically oriented fuse and an diode in series. Within the vertically oriented fuse, the current flow is substantially vertical, i.e. perpendicular to the plane of the substrate. Also, the vertically oriented fuse is placed between top and bottom conductors. This vertical placement of the elements helps to increase density of memory devices built using these unit cells. Also, vertically oriented fuses consume very little lateral area, which helps the density even further. The unit memory cell has two states, an initial state and a written (programmed) state. In the initial state, a resistance of the cell is finite because the vertically oriented fuse is left intact. In the written state, the resistance is infinite because the fuse is blown open. The cell may be programmed by applying a critical voltage across the cell enough to cause the fuse to become open. The states are detected by applying a read voltage across the memory cell.
    Type: Grant
    Filed: August 9, 2001
    Date of Patent: May 20, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Thomas C. Anthony, Lung T. Tran
  • Patent number: 6541312
    Abstract: The present invention is directed to novel antifuse arrays and their methods of fabrication. According to an embodiment of the present invention an array comprises a plurality of first spaced apart rail-stacks having a top semiconductor material. A fill dielectric is located between the first plurality of spaced apart rail-stacks wherein the fill dielectric extends above the top surface of the semiconductor material. An antifuse material is formed on the top of the semiconductor material of the first plurality of spaced apart rail-stacks. A second plurality of spaced apart rail-stacks having a lower semiconductor material is formed on the antifuse material. In the second embodiment of the present invention the array comprises a first plurality of spaced apart rail-stacks having a top semiconductor material. A fill dielectric is located between the first plurality of spaced apart rail-stacks wherein the fill dielectric is recessed below the top surface of the semiconductor material.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: April 1, 2003
    Assignee: Matrix Semiconductor, Inc.
    Inventors: James M. Cleeves, Michael A. Vyvoda, N. Johan Knall
  • Patent number: 6535435
    Abstract: A reference voltage generation circuit is provided which includes a p-channel type MOSFET used as an input transistor to allow a sufficient current to flow through a differential amplifier even if the threshold voltages of MOSFETs used in the differential amplifier significantly increase. A push-pull conversion circuit is coupled to the differential amplifier and has a double end configuration to provide a sufficiently high level to drive a p-channel output buffer. This arrangement allows a stable operation at a sufficiently low power supply voltage even if the threshold voltages of the MOSFETs forming the differential amplifier are high. It also allows quick activation when the power is turned on and provides high stability.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: March 18, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Hitoshi Tanaka, Masakazu Aoki, Shinichiro Kimura, Hiromasa Noda, Tomonori Sekiguchi
  • Patent number: 6535418
    Abstract: A level of a solid state memory device includes main memory and address logic. The address logic is programmed by causing current to flow through an address element of the logic; and irradiating the address element so that the address element changes resistance states.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: March 18, 2003
    Assignee: Hewlett-Packard Development Company, LLP
    Inventor: Josh N. Hogan
  • Patent number: 6522573
    Abstract: According to the present invention, there is provided a solid-state magnetic memory including a semiconductor substrate, a ferromagnetic tunnel junction element facing the semiconductor substrate, first and second wirings sandwiching the ferromagnetic tunnel junction elements from both sides thereof, a third wiring facing the ferromagnetic tunnel junction element, and a diode at least part of which is formed in a surface region of the semiconductor substrate.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: February 18, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Kentaro Nakajima, Minoru Amano
  • Publication number: 20030031047
    Abstract: A one-time programmable unit memory cell includes a vertically oriented fuse and an diode in series. Within the vertically oriented fuse, the current flow is substantially vertical, i.e. perpendicular to the plane of the substrate. Also, the vertically oriented fuse is placed between top and bottom conductors. This vertical placement of the elements helps to increase density of memory devices built using these unit cells. Also, vertically oriented fuses consume very little lateral area, which helps the density even further. The unit memory cell has two states, an initial state and a written (programmed) state. In the initial state, a resistance of the cell is finite because the vertically oriented fuse is left intact. In the written state, the resistance is infinite because the fuse is blown open. The cell may be programmed by applying a critical voltage across the cell enough to cause the fuse to become open. The states are detected by applying a read voltage across the memory cell.
    Type: Application
    Filed: August 9, 2001
    Publication date: February 13, 2003
    Inventors: Thomas C. Anthony, Lung T. Tran
  • Publication number: 20030026158
    Abstract: A memory cell for a two- or a three-dimensional memory array includes first and second conductors and set of layers situated between the conductors. This set of layers includes a dielectric rupture anti-fuse layer having a thickness less than 35 Å and a leakage current density (in the unruptured state) greater than 1 mA/cm2 at 2 V. This low thickness and high current leakage density provide a memory cell with an asymmetric dielectric layer breakdown voltage characteristic. The antifuse layer is formed of an antifuse material characterized by a thickness Tminlife at which the antifuse material is ruptured by a minimum number of write pulses having a polarity that reverse biases diode components included in the memory cell. The average thickness T of the antifuse layer is less than the thickness Tminlife.
    Type: Application
    Filed: December 20, 2001
    Publication date: February 6, 2003
    Applicant: Matrix Semiconductor, Inc.
    Inventors: N. Johan Knall, James M. Cleeves, Igor G. Kouznetsov, Michael A. Vyvoda
  • Publication number: 20030021148
    Abstract: A memory array includes a sensing circuit for sensing bit line current while keeping the voltage of the selected bit line substantially unchanged. The word lines and bit lines are biased so that essentially no bias voltage is impressed across half-selected memory cells, which substantially eliminates leakage current through half-selected memory cells. The bit line current which is sensed arises largely from only the current through the selected memory cell. A noise detection line in the memory array reduces the effect of coupling from unselected word lines to the selected bit line. In a preferred embodiment, a three-dimensional memory array having a plurality of rail-stacks forming bit lines on more than one layer, includes at least one noise detection line associated with each layer of bit lines. A sensing circuit is connected to a selected bit line and to its associated noise detection line.
    Type: Application
    Filed: September 24, 2002
    Publication date: January 30, 2003
    Inventor: Roy E. Scheuerlein
  • Publication number: 20030021147
    Abstract: A level of a solid state memory device includes main memory and address logic. The address logic is programmed by causing current to flow through an address element of the logic; and irradiating the address element so that the address element changes resistance states.
    Type: Application
    Filed: July 24, 2001
    Publication date: January 30, 2003
    Inventor: Josh N. Hogan
  • Patent number: 6509236
    Abstract: A method and apparatus are provided for laser fuseblow protection in transistors, such as silicon-on-insulator (SOI) transistors. The transistors are connected to a fuse. A pair of diodes are connected in series between a high supply and ground. A common connection of the series connected pair of diodes is connected to a common connection of the fuse and transistors. A charge is shunted to the high supply or ground by the pair of diodes with a first voltage a set value above the high supply and a second voltage a set value below the ground. A pair of protection diodes are provided on each side of the fuse with transistors. The transistors are either connected to one side of the fuse or to both sides of the fuse.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: January 21, 2003
    Assignee: International Business Machines Corporation
    Inventors: Anthony Gus Aipperspach, Todd Alan Christensen
  • Patent number: 6504753
    Abstract: A passive element memory array preferably biases selected X-lines to an externally received VPP voltage and selected Y-lines to ground. Unselected Y-lines are preferably biased to VPP minus a first offset voltage, and unselected X-lines biased to a second offset voltage (relative to ground). The first and second offset voltages preferably are identical and have a value of about 0.5 to 2 volts. The VPP voltage depends upon the memory cell technology used, and preferably falls within the range of 5 to 20 volts. The area otherwise required for an on-chip VPP generator and saves the power that would be consumed by such a generator. In addition, the operating temperature of the integrated circuit during the programming operation decreases, which further decreases power dissipation. When discharging the memory array, the capacitance between layers is preferably discharged first, then the layers are discharged to ground.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: January 7, 2003
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Roy E. Scheuerlein, Matthew P. Crowley
  • Publication number: 20030002321
    Abstract: A high speed, low power Static Random Access Memory (SRAM) Array, which includes a 4T cell with two integrated Schottky Barrier Diodes (SBD) is disclosed. In a preferred embodiment, the cell bulk area and speed advantage is 30%, and ac power saving is 75% compared with the 6T CFET cell. The physical construct of the 4T cell saves capacitance in all critical nodes intra or inter cell wise, eliminates pass transistors, reduces the well noises. Typical embodiment uses a 0.15-um-rule based layout, and 1.5V supports operation at 5 ns cycles. SBD are used extensively with CFET to form a CMOS version of the Diode Transistor Logic circuitry. Generic control functions can be implemented including NAND gates, level shifting, decoding, voltage generator, ESD and latch-up protection, leakage control, and dynamic VT setting while in operation. Product applications include DRAM, SRAM, PLD, DRAM, CAM, Flash, Computing, Networking, and Communication devices as standalone system component or embedded into any ASIC.
    Type: Application
    Filed: June 15, 2001
    Publication date: January 2, 2003
    Inventor: Augustine Wei-Chun Chang
  • Publication number: 20020196659
    Abstract: A data storage device is disclosed that comprises a cross-point memory array formed on a dielectric substrate material. The cross-point memory array comprises first and second sets of transverse electrodes separated by a storage layer including at least one semiconductor layer. The storage layer forms a non-volatile memory element at each crossing point of electrodes from the first and second sets. Each memory element can be switched between low and high impedance states, representing respective binary data states, by application of a write signal in the form of a predetermined current density through the memory element. Each memory element includes a diode junction formed in the storage layer, at least whilst in the low impedance state. A plurality of the data storage devices can be stacked and laminated into a memory module providing inexpensive high capacity data storage.
    Type: Application
    Filed: June 5, 2001
    Publication date: December 26, 2002
    Inventors: Terril N. Hurst, Craig Perlov, Carol Wilson, Carl Taussig
  • Publication number: 20020181276
    Abstract: A method of repairing a light-emitting device capable of performing high quality image display even if pinholes are formed when forming an organic compound layer is provided. Device contamination can be prevented during repair. By applying a reverse bias voltage to an organic light emitting element during fixed periods of time, the electric current flowing in the EL element during application of the reverse bias voltage is reduced. Further, by forming a cathode so as to contain as little as possible of the high mobility ions Li and Na, contamination of the device when the reverse bias is applied can be prevented. It is preferable to use AlMg and MgAg for this type of cathode.
    Type: Application
    Filed: May 30, 2002
    Publication date: December 5, 2002
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Shunpei Yamazaki
  • Patent number: 6490193
    Abstract: A negative differential resistance device is provided that includes a first barrier, a second barrier and a third barrier. A first quantum well is formed between the first and second barriers. A second quantum well is formed between the second and third barriers.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: December 3, 2002
    Assignee: Raytheon Company
    Inventors: Jan Paul van der Wagt, Gerhard Klimeck
  • Patent number: 6480413
    Abstract: Two resonant tunneling diodes with hysteretic folding V-I characteristics are connected in series. The node voltage and the series current of the cell determine the memory state and there can be a large number of states. During writing, one writing pulse sets the pull-down RTD to one of the positive differential resistance region of the hysteretic V-I characteristic, and a second writing pulse sets the pull-up RTD to one of positive differential resistance region. During writing, the series current is sensed by measuring the colon ground current.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: November 12, 2002
    Assignee: Epitaxial Technologies LLC
    Inventor: Hung Chang Lin