Three-dimensional Magnetic Array Patents (Class 365/130)
  • Patent number: 6992910
    Abstract: A “toggling” type of magnetic random access memory (MRAM) has memory stacks arranged in the X-Y plane on the MRAM substrate with each memory stack having a plurality of toggle memory cells stacked along the Z axis. Each memory stack is located at an intersection region between two orthogonal write lines. Each cell in the stack is a “toggle” cell that has its synthetic antiferromagnet (SAF) free layer easy axis of magnetization aligned nonparallel with the X and Y axes and angularly spaced about the Z axis from the easy axes of magnetization of all the other SAF free layers in the stack. Each cell in a stack is magnetically separated from adjacent cells in the stack by a nonmagnetic separation layer. The magnetization direction of the free layer in a selected memory cell in a stack can be switched without switching the magnetization directions of the free layers in the other memory cells in the stack.
    Type: Grant
    Filed: July 20, 2005
    Date of Patent: January 31, 2006
    Assignee: Maglabs, Inc.
    Inventors: Kochan Ju, Oletta Allegranza
  • Patent number: 6990004
    Abstract: A read block is formed from a plurality of TMR elements stacked in the vertical direction. One terminal of each TMR element in the read block is connected to a source line through a read select switch. The source line extends in the Y-direction and is connected to a ground point through a column select switch. The other terminal of each TMR element is independently connected to a corresponding one of read/write bit lines. Each read/write bit line extends in the Y-direction and is connected to a read circuit through the column select switch.
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: January 24, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoshihisa Iwata
  • Patent number: 6982894
    Abstract: A structure and method for forming a magnetic memory having a number N of levels of magnetic memory cells by forming a plurality of levels of magnetic memory cells, each level including at least one magnetic memory core structure having first and second surfaces, forming a first access conductor connecting to the first surface, forming a second access conductor connecting to the second surface, wherein N+1 access conductors are formed per number N of levels of magnetic memory cells. The structure comprises a plurality of levels of magnetic memory cells, each level including at least one magnetic memory having a number N of levels of magnetic memory cells, including a magnetic memory core structure having first and second surfaces, the first and second surfaces each connecting to an individual access conductor, wherein N+1 access conductors are employed per number N of levels of magnetic memory cells.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: January 3, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Garry Mercaldi
  • Patent number: 6937497
    Abstract: A “toggling” type of magnetic random access memory (MRAM) has memory stacks arranged in the X-Y plane on the MRAM substrate with each memory stack having a plurality of toggle memory cells stacked along the Z axis. Each memory stack is located at an intersection region between two orthogonal write lines. Each cell in the stack is a “toggle” cell that has its synthetic antiferromagnet (SAF) free layer easy axis of magnetization aligned nonparallel with the X and Y axes and angularly spaced about the Z axis from the easy axes of magnetization of all the other SAF free layers in the stack. Each cell in a stack is magnetically separated from adjacent cells in the stack by a nonmagnetic separation layer. The magnetization direction of the free layer in a selected memory cell in a stack can be switched without switching the magnetization directions of the free layers in the other memory cells in the stack.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: August 30, 2005
    Assignee: Maglabs, Inc.
    Inventors: Kochan Ju, Oletta Allegranza
  • Patent number: 6762950
    Abstract: A ferroelectric or electret volumetric memory device with a memory material provided in sandwich between first and second electrode layers with stripe-like electrodes forming word lines and bit lines of a matrix-addressable memory array, memory cells are defined in volumes of memeory material in between two crossing word lines and bit lines and a plurality of memory arrays are provided in a stacked arrangement. A stack of memory arrays is formed by tow or more ribbon-like structures, which are folded and/or braided into each other. Each ribbon-like structure includes a flexible substrate of non-conducting material and the electrode layers respectively provided on each surface of the substrate and including the parallel strip-like electrodes extending along the ribbon-like structure.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: July 13, 2004
    Assignee: Thin Film Electronics ASA
    Inventors: Hans Gude Gudesen, Per-Erik Nordal
  • Patent number: 6665205
    Abstract: The invention includes an apparatus and a method that provides a shared global word line MRAM structure. The MRAM structure includes a first bit line conductor oriented in a first direction. A first sense line conductor is oriented in a second direction. A first memory cell is physically connected between the first bit line conductor and the first sense line conductor. A global word line is oriented in substantially the second direction, and magnetically coupled to the first memory cell. A second bit line conductor is oriented in substantially the first direction. A second sense line conductor is oriented in substantially the second direction. A second memory cell is physically connected between the second bit line conductor and the second sense line conductor. The global word line is also magnetically coupled to the second memory cell. The first memory cell and the second memory cell can be MRAM devices.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: December 16, 2003
    Assignee: Hewlett-Packard Development Company, LP.
    Inventors: Heon Lee, Fred Perner
  • Patent number: 6643159
    Abstract: A cubic memory array is fabricated on a substrate having a planar surface. The cubic memory array includes a plurality of first select-lines organized in more than one plane parallel to the planar surface. A plurality of second select-lines is formed in pillars disposed orthogonal to the planer surface of the substrate. A plurality of memory cells are respectively coupled to the plurality of first and plurality of second select-lines.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: November 4, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Peter Fricke, Andrew L. Van Brocklin, Daryl Anderson
  • Patent number: 6639821
    Abstract: A memory device includes an array of memory elements overlying a plurality of driver cells. Vias through an insulating layer connect the driver cells to the memory elements. The vias are distributed over the area of the array to connect the individual driver cells to the respective row and and/or column conductors of the memory array.
    Type: Grant
    Filed: July 26, 2002
    Date of Patent: October 28, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Stephen J. Battersby
  • Publication number: 20030043614
    Abstract: A structure and method for forming a magnetic memory having a number N of levels of magnetic memory cells by forming a plurality of levels of magnetic memory cells, each level including at least one magnetic memory core structure having first and second surfaces, forming a first access conductor connecting to the first surface, forming a second access conductor connecting to the second surface, wherein N+1 access conductors are formed per number N of levels of magnetic memory cells. The structure comprises a plurality of levels of magnetic memory cells, each level including at least one magnetic memory having a number N of levels of magnetic memory cells, including a magnetic memory core structure having first and second surfaces, the first and second surfaces each connecting to an individual access conductor, wherein N+1 access conductors are employed per number N of levels of magnetic memory cells.
    Type: Application
    Filed: October 22, 2002
    Publication date: March 6, 2003
    Inventor: Garry Mercaldi
  • Publication number: 20030026121
    Abstract: A very high density field programmable memory is disclosed. An array is formed vertically above a substrate using several layers, each layer of which includes vertically fabricated memory cells. The cell in an N level array may be formed with N+1 masking steps plus masking steps needed for contacts. Maximum use of self alignment techniques minimizes photolithographic limitations. In one embodiment the peripheral circuits are formed in a silicon substrate and an N level array is fabricated above the substrate.
    Type: Application
    Filed: September 23, 2002
    Publication date: February 6, 2003
    Inventors: Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, Paul Michael Farmwald, James M. Cleeves
  • Patent number: 6515888
    Abstract: A low-cost memory cell array includes multiple, vertically-stacked layers of memory cells. In one form, each memory cell is characterized by a small cross-sectional area and a read current less than 6.3 microamperes. The resulting memory array has a slow access time and is well-suited for digital media storage, where access time requirements are low and the dramatic cost reductions associated with the disclosed memory arrays are particularly attractive. In another form, each memory cell includes an antifuse layer and diode components, wherein at least one diode component is heavily doped (to a dopant concentration greater than 1019/cm3), and wherein the read current is large (up to 500 mA).
    Type: Grant
    Filed: August 13, 2001
    Date of Patent: February 4, 2003
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, P. Michael Farmwald, N. Johan Knall
  • Publication number: 20030021142
    Abstract: A memory cell for a three-dimensional intergrated circuit memory is disclosed. The cell includes a very highly doped semiconductor regions with a doping level of 1020 atoms cm−3 or higher. An antifuse region is disposed between the heavily doped region and a more lightly doped region.
    Type: Application
    Filed: June 27, 2002
    Publication date: January 30, 2003
    Inventor: N. Johan Knall
  • Patent number: 6483736
    Abstract: A very high density field programmable memory is disclosed. An array is formed vertically above a substrate using several layers, each layer of which includes vertically fabricated memory cells. The cell in an N level array may be formed with N+1 masking steps plus masking steps needed for contacts. Maximum use of self alignment techniques minimizes photolithographic limitations. In one embodiment the peripheral circuits are formed in a silicon substrate and an N level array is fabricated above the substrate.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: November 19, 2002
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, Paul Michael Farmwald, James M. Cleeves
  • Patent number: 6473328
    Abstract: A structure and method for forming a magnetic memory having a number N of levels of magnetic memory cells by forming a plurality of levels of magnetic memory cells, each level including at least one magnetic memory core structure having first and second surfaces, forming a first access conductor connecting to the first surface, forming a second access conductor connecting to the second surface, wherein N+1 access conductors are formed per number N of levels of magnetic memory cells. The structure comprises a plurality of levels of magnetic memory cells, each level including at least one magnetic memory having a number N of levels of magnetic memory cells, including a magnetic memory core structure having first and second surfaces, the first and second surfaces each connecting to an individual access conductor, wherein N+1 access conductors are employed per number N of levels of magnetic memory cells.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: October 29, 2002
    Assignee: Micron Technology, Inc.
    Inventor: Garry Mercaldi
  • Publication number: 20020075719
    Abstract: A low-cost memory cell array includes multiple, vertically-stacked layers of memory cells. In one form, each memory cell is characterized by a small cross-sectional area and a read current less than 6.3 microamperes. The resulting memory array has a slow access time and is well-suited for digital media storage, where access time requirements are low and the dramatic cost reductions associated with the disclosed memory arrays are particularly attractive. In another form, each memory cell includes an antifuse layer and diode components, wherein at least one diode component is heavily doped (to a dopant concentration greater than 1019/cm3), and wherein the read current is large (up to 500 mA).
    Type: Application
    Filed: August 13, 2001
    Publication date: June 20, 2002
    Inventors: Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, P. Michael Farmwald, N. Johan Knall
  • Patent number: 6385074
    Abstract: An integrated circuit device includes a three-dimensional memory array and array terminal circuitry for providing to selected memory cells of the array a write voltage different from a read voltage. Neither voltage is necessarily equal to a VDD power supply voltage supplied to the integrated circuit. The write voltage, particularly if greater than VDD, may be generated by an on-chip voltage generator, such as a charge pump, which may require an undesirably large amount of die area, particularly relative to a higher bit density three-dimensional memory array formed entirely in layers above a semiconductor substrate. In several preferred embodiments, the area directly beneath a memory array is advantageously utilized to layout at least some of the write voltage generator, thus locating the generator near the selected memory cells during a write operation.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: May 7, 2002
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, Paul Michael Farmwald, James M. Cleeves
  • Patent number: 5907581
    Abstract: A one-dimensional data stream is encoded into a two-dimensional data array with reduced high frequency components, for recording on a two-dimensional recording device, such as a holographic storage device. A two-dimensional data array read from the two-dimensional recording device is decoded into the original one-dimensional data stream. To encode, a one-dimensional data stream is partitioned into a plurality of chunks of data. Each chunk of data is partitioned into a plurality of groups of bits. Each group of bits is encoded into a two dimensional data array according to a predefined constraint. A plurality of two-dimensional data arrays are concatenated into a data strip. A plurality of data strips are then assembled into a complete two-dimensional data block. To decode, a two-dimensional data stream is partitioned into multiple small two-dimensional arrays. Each array is decoded into a multi-bit group. In one embodiment, this decoding is a function of other nearby groups.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: May 25, 1999
    Assignee: International Business Machines Corporation
    Inventors: Jonathan James Ashley, Brian Harry Marcus
  • Patent number: 5260893
    Abstract: Strips of fabric material are attached along the edges of an array of magnetic cores on a substrate with the strips having an upstanding ridge aligned parallel to the edges of the array. The material of the fabric serves as a guide for threading wires through the cores, and also serves as an attachment support for the wires to keep them from lifting free from the support after being inserted through the cores. The guide/supports are relatively simple, strong, durable, resistant to deterioration, and provide an inexpensive guide and support for the wires of the core memory.
    Type: Grant
    Filed: December 27, 1991
    Date of Patent: November 9, 1993
    Assignee: SCI Systems, Inc.
    Inventor: Mahmoud Ghaneei
  • Patent number: 4575825
    Abstract: Disclosed is a semiconductor memory device which is one of three types of semiconductor memory devices, one operable only in page mode, one operable only in nibble and one operable selectively in page mode or nibble mode, being obtained from a partially unconnected semiconductor memory device through alternations in a portions in wiring. The semiconductor memory device includes first and second internal column address strobe signal generator. The second internal column address strobe signal generator has at the first stage thereof a NAND circuit one of inputs to which determines the type of the semiconductor memory device depending on which of three kinds of signals is selected as the input. Selection of such an input is effected by an aluminum wiring process using a mask. Such selection of the input causes variation in the input response characteristics of the output of the second internal column address strobe signal generator, thus providing a desired response appropriate for the selected mode or modes.
    Type: Grant
    Filed: January 4, 1984
    Date of Patent: March 11, 1986
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hideyuki Ozaki, Kazuhiro Shimotori, Hideshi Miyatake
  • Patent number: 4532610
    Abstract: A small, very low cost, wide margin core memory couples a return current drive scheme with a crossover-free sense winding extending parallel to the Y drive conductors to eliminate the assembly time and wasted substrate space associated with sense winding crossovers. The return currents generate small noise signals which cancel with partial select noise signals to provide noise signals comparable to a 3 wire, 3D bow tie sense winding.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: July 30, 1985
    Assignee: Ampex Corporation
    Inventor: Thomas J. Gilligan
  • Patent number: 4523302
    Abstract: A highly efficient core memory drive system passes currents down a selected X and Y conductor and divides the currents for return through the unselected drive wires in the same X or Y dimension. The drive conductors are coupled to drive and sink switches at a drive end and the X conductors are connected together at an opposite common end and the Y conductors are connected together at an opposite common end. Resistors provide a current path between the drive end of each X conductor and an X resistor bus and between the drive end of each Y conductor and a Y resistor bus. A pair of switching transistors including a sink transistor and a drive transistor is connected to a drive end of each conductor to generate a drive current therein. The drive current divides equally among the unselected conductors at the common end to return through the unselected conductors and through the resistors to the resistor bus.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: June 11, 1985
    Assignee: Ampex Corporation
    Inventor: Thomas J. Gilligan
  • Patent number: 4437173
    Abstract: A core memory utilizes an auxiliary core that is driven concurrently with selected data cores to increase tolerances by automatically tracking the peaking time and the output magnitude. Wide variations in both the magnitude and duration of core output switching signals are compensated by use of the auxiliary core to control the sensing strobe time during a read part cycle and drive current duration during both read and write part cycles. Subtracting half of the auxiliary core output switching signal from a selected data core output switching signal normalizes the difference about zero volts with a one being indicated by the presence of a positive voltage and a zero by a negative voltage. With the reference threshold at zero there is no precise adjustment. Since the peak of the auxiliary core output tracks the peak of the selected data core output, substantial changes in the peaking and switching times do not interfere with accurate determinations of data core data states.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: March 13, 1984
    Assignee: Ampex Corporation
    Inventors: Jules E. Canel, Thomas J. Gilligan
  • Patent number: 4374432
    Abstract: Organizations are disclosed for driving bit lines of a two-line 21/2D coincident current magnetic core memory in which a bit line not used for reading a bit out of a core is placed physically in parallel with the bit line driven by half select current to approximate in the unused line the capacitive and inductive coupling of the driven line with the word drive line. That coupling produces in the unused line the same noise (crosstalk) produced in the driven bit line by the word drive pulse. The crosstalk signal in the unused line is subtracted from the signal in the driven bit line before amplification and detection. The unused line may be a separate dummy line, or simply another bit line not being used for the bit being read out. In the case of paired bit lines used for common mode rejection of the bit drive signal, a second pair of unused bit lines is arranged in parallel for crosstalk cancellation.
    Type: Grant
    Filed: May 29, 1979
    Date of Patent: February 15, 1983
    Assignee: Electronic Memories and Magnetics Corporation
    Inventors: Bernard A. Kenner, John R. Conaway
  • Patent number: 4328564
    Abstract: A processor controlled postage meter includes memories for storage of meter account balance data. Thermal security of the balance data is maintained through the employment of magnetic core memories constructed to withstand high temperatures which may be generated during a fire at the location of the meter. The magnetic core memory includes a matrix of toroids arranged in a plane and encased within ceramic cement for thermal insulation. The toroids are preferably formed of a non-oxidized pure metal magnetic alloy having a Curie temperature of at least 650 degrees Celsius.
    Type: Grant
    Filed: November 26, 1979
    Date of Patent: May 4, 1982
    Assignee: Pitney Bowes Inc.
    Inventor: Roger W. Pryor
  • Patent number: 4161037
    Abstract: A ferrite core memory in the form of a hollow plait of ferrite matrices. ferrite matrices comprise ferrite cores interwoven with coordinate wires and wires forming readout and inhibition windings. The hollow plait consists of alternating squares of ferrite matrices connected at their edges and formed into a hollow cylindrical plait. The diagonal lines of the matrices extend axially and transversely of the plait. The coordinate wires interweaving the ferrite cores extend along orthogonally intersecting helical lines lying on the cylindrical surface of the plait. The outgoing leads of the readout and inhibition windings are distributed longitudinally along the plait.
    Type: Grant
    Filed: January 17, 1977
    Date of Patent: July 10, 1979
    Assignee: Vychislitelny Tsentr Sibirskogo Otdelenia Akademii Nauk SSSR
    Inventors: Jury E. Seleznev, Jury A. Burkin, Sergei V. Kuzmin
  • Patent number: 4096583
    Abstract: A large, 2 wire, 21/2D core memory includes four, 1K (1024) by 1280, core frames with 1280 Y conductors each stringing and inductively coupling a column of 1024 cores in each of the four frames and 4K orthogonal X conductors each stringing and inductively coupling one row of 1280 cores. A word position within the memory is defined by 5 pairs of Y conductors, a corresponding X conductor from each frame, and selection of relative current directions in the Y conductors. Reading of a 20 bit word is accomplished with 5 sense amplifiers in four rapid succession read sub-operations. Writing is accomplished in two sub-operations by separately controlling partial select digit currents in each of the 5 pairs of Y conductors. A bidirectional X drive and switching arrangement utilizes overlapping X drive currents and shared circuitry to maximize memory speed and reduce electronic components costs.
    Type: Grant
    Filed: October 15, 1976
    Date of Patent: June 20, 1978
    Assignee: Ampex Corporation
    Inventors: Kurt Wright, Thomas J. Gilligan
  • Patent number: RE30395
    Abstract: A large, 2 wire, 21/2D core memory includes four, 1K (1024) by 1280, core frames with 1280 Y conductors each stringing and inductively coupling a column of 1024 cores in each of the four frames and 4K orthogonal X conductors each stringing and inductively coupling one row of 1280 cores. A word position within the memory is defined by 5 pairs of Y conductors, a corresponding X conductor from each frame, and selection of relative current directions in the Y conductors. Reading of a 20 bit word is accomplished with 5 sense amplifiers in four rapid sucession read sub-operations. Writing is accomplished in two sub-operations by separately controlling partial select digit currents in each of the 5 pairs of Y conductors. A bidirectional X drive and switching arrangement utilizes overlapping X drive currents and shared circuitry to maximize memory speed and reduce electronic components costs.
    Type: Grant
    Filed: January 15, 1979
    Date of Patent: September 2, 1980
    Assignee: Ampex Corporation
    Inventors: Kurt O. Wright, Thomas J. Gilligan