Diodes Patents (Class 365/175)
  • Patent number: 5889694
    Abstract: A read-only data storage and retrieval device is presented having no moving parts and requiring very low power. Addressing can be accomplished sequentially where the address increments automatically or can be accomplished randomly. High density storage is achieved through the use of a highly symmetric diode matrix that is addressed in both coordinate directions; its symmetry makes the Dual-addressed Rectifier Storage (DRS) Array very scaleable, particularly when made as an integrated circuit. For even greater storage flexibility, multiple digital rectifier storage arrays can be incorporated into the device, one or more of which can be made removable and interchangeable.
    Type: Grant
    Filed: May 27, 1997
    Date of Patent: March 30, 1999
    Inventor: Daniel R. Shepard
  • Patent number: 5883829
    Abstract: A memory system is organized as a matrix including a memory cell at each intersection of a bit line with write and read word lines Each memory cell comprises a first FET 20 having its gate coupled to a write word line and its drain coupled to a bit line, a second FET 22 having its source coupled to the bit line and its drain coupled to a read word line, and first and second negative resistance devices 24,26 coupled in series between a supply voltage and a substrate voltage, the common point SN of the series-connected negative resistance devices being coupled to the source of the first PET and to the gate of the second FET. Preferably, the first FET 20 is a p-channel device, the second FET 22 is an n-channel device, and the first and second negative resistance devices 24,26 are RTDs. In a second embodiment, a memory system has a memory cell at each intersection of a bit line with a word line.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: March 16, 1999
    Assignee: Texas Instruments Incorporated
    Inventor: Jan P. van der Wagt
  • Patent number: 5877983
    Abstract: A negative programming voltage is selectively applied to a word line of a nonvolatile memory by initially charging all of the word lines with the negative programming voltage. When the negative programming voltage is turned off, the word lines assume a floating state. Thereafter, a positive voltage is added to all the non-selected word lines in order to compensate for the negative charges.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: March 2, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Georg Tempel
  • Patent number: 5875127
    Abstract: A memory array circuit has a matrix of column lines and row lines. A plurality of non-volatile storage capacitors, each having a floating gate for the storage of charges, are arranged in the matrix. Each storage capacitor has a data node and a voltage node, with a floating gate therebetween. Each of the plurality of non-volatile storage capacitors has an associated column line and an associated row line, with the voltage node connected to the associated row line. A diode connects the data node of a storage capacitor to its associated column line. A first decoder decodes a first address signal and selects one of the column lines. A second decoder decodes a second address signal, and generates a row output signal, with each row output signal of the second decoder having a corresponding row line.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: February 23, 1999
    Inventor: Ronald Loh-Hwa Yin
  • Patent number: 5869845
    Abstract: A resonant tunneling diode stack used as a memory cell stack (X0-Xn) with sequential read out of bits of data cells (X1-Xn) by increasing ramp rates to transfer the stored bit to a lowest ramp rate cell (X0).
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: February 9, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Jan Paul Vander Wagt, Hao Tang
  • Patent number: 5856708
    Abstract: A method of manufacturing an SRAM cell with polysilicon diode loads using standard logic technology processing. A P+ polysilicon area and an N+ polysilicon are forms a lateral PN junction. In standard logic technology processing the lateral PN junction is shorted out. In the present invention the lateral PN junction is allowed to function as a polysilicon diode load and an ancilliary lateral PN junction is shorted using a polycide cap layer.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: January 5, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Donald L. Wollesen
  • Patent number: 5847988
    Abstract: A process and structure are disclosed for a programmable array for use in a read-only memory comprising diode elements and shorted diode elements. The elements are connected across bit and wordlines. The invention utilizes lateral polysilicon diodes and metal silicide layer bridging the junction of pre-selected diodes to short pre-selected diode elements. Programming is accomplished by either forming the silicide layer across the junctions of pre-selected diodes or removing the silicide layer from the junctions of pre-selected diodes.
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: December 8, 1998
    Assignee: International Business Machines Corporation
    Inventors: Gordon M. Babson, Allen W. Brouillette, Richard J. Evans, Robert J. Finch, Philip H. Noel, Richard J. Ross
  • Patent number: 5831893
    Abstract: A read-only memory cell capable of being programmed by the application of radiant energy. The memory cell includes a trimmable resistor, a diode and a latch. In one embodiment, the cathode of the diode is in electrical communication with a first terminal of the resistor and the anode of the diode is in electrical communication with the second terminal of the resistor. The latch has an input terminal in electrical communication with the second terminal of the resistor and an output terminal. The latch is in a first state when the trimmable resistor is untrimmed and is in a second state when the trimmable resistor is trimmed. In one embodiment, the trimmable resistor is trimmable by laser energy. The invention also relates to a method of storing data in a memory cell.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: November 3, 1998
    Assignee: Sipex Corporation
    Inventor: Jeffrey B. Van Auken
  • Patent number: 5825687
    Abstract: A memory array circuit has two memory sections. Each memory section has a matrix of column lines and row lines. A plurality of memory cells are arranged in the matrix, with each memory cell comprising a tunnel diode connected in series with a load, with a data node therebetween. The impedance characteristics of the tunnel diode and the load is such that at the data node, they intersect to form two or more points of stability. In one embodiment, a conventional access transistor is used to write data into and to read data out of the memory cell. In another embodiment an avalanche diode is used to write data into and to read data out of the memory cell.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: October 20, 1998
    Inventor: Ronald Loh-Hwa Yin
  • Patent number: 5822240
    Abstract: A novel ferroelectric random access memory structure which comprises a capacitor consisting of upper and lower plane electrodes and a ferroelectric inserted therebetween, and a transistor comprising a means of inducing the capacitor to polarization and maintaining it, connected with at least one of the electrodes, wherein the electric potential of the upper electrode is equalized with that of the lower electrode, thereby preventing the polarization reversal caused by pyroelectric charges.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: October 13, 1998
    Assignee: Samsung Electronics Co. Ltd.
    Inventor: In-kyung Yoo
  • Patent number: 5822235
    Abstract: A rectifying transfer gate circuit includes first and second field effect transistors and one diode. The source of the first field effect transistor is coupled to a first input node and the gate thereof is coupled to a second input node. Meanwhile, the source of the second field effect transistor is coupled to the second input node and the gate thereof is coupled to the first input node. The diode is coupled between the common drain of the first and second field effect transistors and an output node, so as to increase the speed of the operation in the application circuit utilizing the above rectifying transfer gate circuit.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: October 13, 1998
    Assignee: SamSung Electronics Co. Ltd.
    Inventor: Takashi Nakashima
  • Patent number: 5818749
    Abstract: A memory array using structure changing memory elements in a reverse biased diode array is disclosed. A memory cell is programmed and read by reverse biasing the diode to overcome the diode's breakdown voltage. The disclosed reversed biased diode array exhibits much less substrate current leakage than a similar forward biased diode array.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: October 6, 1998
    Assignee: Micron Technology, Inc.
    Inventor: Steven T. Harshfield
  • Patent number: 5818779
    Abstract: A board includes a plurality of integrated circuits operating at a first supply potential to be supplied. The board has a potential adaptation configuration with an output potential being the first supply potential and an input potential being a second supply potential to be supplied to the board.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: October 6, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Thomas Von Der Ropp
  • Patent number: 5814853
    Abstract: A floating gate diode which can be used as a sourceless memory cell, and which may be arranged into an array of memory cells is disclosed. The floating gate diode comprises: a drain region formed in a substrate; an oxide overlying and associated with the drain region; and a floating gate overlying the oxide. Upon application of a voltage to the drain, a current between the drain and substrate is induced in proportion to an amount of electrons stored on the gate. The cells may be arranged into an array which comprises a substrate having a surface; a plurality of drain regions, one of said drain regions respectively corresponding to one of the plurality of cells, formed in the substrate; an oxide region overlying the plurality of drain regions on the surface of the substrate; and a plurality of floating gates overlying the oxide and respectively associated with the plurality of drain regions.
    Type: Grant
    Filed: January 22, 1996
    Date of Patent: September 29, 1998
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Jian Chen
  • Patent number: 5768175
    Abstract: In a ferrolectric memory, semiconductor memory cells are arranged in a matrix array of rows and columns and connected respectively to plate lines, word lines and bit lines for changing polarization states of the capacitor of an addressed memory cell in response to operating voltages. First, second and third terminals are provided. A first set of conducting devices establishes branched paths from the first terminal to the plate lines when a first potential is applied to the first terminal, and a second set of conducting devices establishes branched paths from the second terminal to the word lines when a second potential is applied to the second terminal. A third set of conducting devices establishes branched paths from the third terminal to the bit lines when a third potential is applied to the third terminal. If the ferroelectric capacitor of at least one of the memory cells is short-circuited, a sufficient current will flow into the cell to heal the faulty condition.
    Type: Grant
    Filed: April 24, 1997
    Date of Patent: June 16, 1998
    Assignee: NEC Corporation
    Inventor: Sota Kobayashi
  • Patent number: 5745407
    Abstract: A transistorless memory cell for storing information as one of two possible bistable current states comprises (i) at least one first transistorless device exhibiting N-type negative differential resistance, including a high-impedance region, a low-impedance region and a negative-resistance region and having a polarity and (ii) at least one second transistorless device exhibiting an exponential or linear current-voltage characteristic and coupled to the first transistorless device. The read/write operation of the transistorless memory cell is performed in a current mode.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: April 28, 1998
    Assignee: California Institute of Technology
    Inventors: Harold J. Levy, Thomas C. McGill
  • Patent number: 5737259
    Abstract: A diode type read only memory (ROM) includes a diode as a memory cell. The diode is a logic level "on" memory cell and coupled to one of the word lines and one of the bit lines of the ROM. A relative high voltage is given to the bit line coupled to the diode and a relative low voltage is given to the corresponding word line. Therefore, the data saved in the diode can be read out.
    Type: Grant
    Filed: December 31, 1996
    Date of Patent: April 7, 1998
    Assignee: United Microelectronics Corporation
    Inventor: Kuang Yeh Chang
  • Patent number: 5717627
    Abstract: The optical memory device of the present invention comprises a photodetector device which generates a current when light is incident thereon and a light-emitting device which is connected to the photodetector device in series so as to emit light upon receiving a supply of current from the photodetector device and feed back thus emitted light toward the photodetector device.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: February 10, 1998
    Assignee: Hamamatsu Photonics K.K.
    Inventor: Yoshihiko Mizushima
  • Patent number: 5717629
    Abstract: A memory array circuit has a matrix of column lines and row lines. A plurality of storage capacitors are arranged in the matrix, with each storage capacitor having a data node and a voltage node. Each of the plurality of storage capacitors has an associated column line and an associated row line, with the voltage node connected to the associated row line. A diode connects the data node of a storage capacitor to its associated column line. A first decoder decodes a first address signal and selects one of the column lines. A second decoder decodes a second address signal, and generates a row output signal, with each row output signal of the second decoder having a corresponding row line. A plurality of voltage control circuits is provided with each voltage control circuit receiving one of the plurality of row output signals, and for applying a control signal to a corresponding row line, in response to a data read signal, a data write to one state signal or a data write to another state signal.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: February 10, 1998
    Inventor: Ronald Loh-Hwa Yin
  • Patent number: 5699294
    Abstract: A semiconductor memory device comprises a plurality of memory cells each including an element with a potential barrier serving as a switching element and a capacitor one terminal of which is connected to the switching element. The memory cells are disposed in a matrix arrangement. Terminals of the respective capacitors which are not connected to the switching elements are connected to each other in intersection with bit lines in the memory cell arrangement to thereby form word lines. Alternatively, the terminals of the respective capacitors connected to the switching elements may be connected to each other in intersection with the bit lines to thereby form word lines.
    Type: Grant
    Filed: October 25, 1995
    Date of Patent: December 16, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Yamada, Yohji Watanabe
  • Patent number: 5691934
    Abstract: An extremely compact dynamic memory cell (200) includes a capacitor (204) or any other suitable stored charge device, and a diode (208) such as a Zener diode, a pair of parallel, reverse-connected diodes, or any other suitable voltage dropping device having substantially definite voltage drops when conducting in each direction. The capacitor and Zener diode are connected in series between a Row Select line (202) and a Column Bit line (210). These structures are suitable for fabrication by any of a variety of processes used to fabricate conventional semiconductor DRAMs. The memory cell is replicated millions of times and arrayed in rows and columns as in conventional one-transistor MOSFET DRAM memories to form a memory integrated circuit. Rows of cells are accessed by asserting the corresponding Row Select line, and columns are accessed by asserting the Column Bit line.
    Type: Grant
    Filed: July 13, 1995
    Date of Patent: November 25, 1997
    Inventor: Barry G. Douglass
  • Patent number: 5684737
    Abstract: A static random access memory (SRAM) cell includes a bistable diode and a load device serially connectable between two voltage potentials (VDD, Ground) with a gate device (field effect transistor) connected between a bit line and a common terminal of the bistable diode and load device and a control terminal of the gate device connected to a word line. The bistable diode includes a GeSi structure between a p-doped semiconductor region and a spaced n-doped semiconductor region. The GeSi structure can be a GeSi/Si superlattice and a .delta.-doped tunnel junction, a Ge.sub.x Si.sub.1-x multiple well structure, or a .delta.-doped tunnel junction.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: November 4, 1997
    Assignee: The Regents of the University of California
    Inventors: Kang L. Wang, Xinyu Zheng, Timothy K. Carns
  • Patent number: 5675533
    Abstract: A latch-type SRAM memory cell having a number of MOS transistors arranged to maintain symmetry with each other circuitwise, in which the source regions of the MOS transistors are arranged so as to be adjacent semiconductor regions of opposite conductivity with respect thereto. Zener diodes are formed between the adjacent source and semiconductor regions with each of these Zener diodes being connected between their respective source regions and a power supply. Since current to each source region of paired MOS transistors flows effectively to the power supply or ground side via a Zener diode using a tunneling effect, a rise in the source region potential can be reduced, and an increase in the transistor threshold value can be controlled. In this way, symmetry of the paired transistors can be maintained, and the performance of the memory cell, e.g., memory cell data retention ability and drive current ability, can be increased.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: October 7, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Takayuki Niuya, Yuji Iwasawa
  • Patent number: 5673218
    Abstract: A read-only data storage and retrieval device is presented having no moving parts and requiring very low power. Addressing can be accomplished sequentially where the address increments automatically or can be accomplished randomly. High density storage is achieved through the use of a highly symmetric diode matrix that is addressed in both coordinate directions; its symmetry makes the Dual-addressed Rectifier Storage (DRS) Array very scaleable, particularly when made as an integrated circuit. For even greater storage flexibility, multiple digital rectifier storage arrays can be incorporated into the device, one or more of which can be made removable and interchangeable.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: September 30, 1997
    Inventor: Daniel R. Shepard
  • Patent number: 5671182
    Abstract: A memory array circuit has two memory sections. Each memory section has a matrix of column lines and row lines. A plurality of storage latches are arranged in the matrix, with each storage latch having a data node, and a voltage node. Each of the plurality of storage latches has an associated column line and an associated row line, with the voltage node connected to the associated row line. A diode connects the data node of a storage latch to its associated column line. A first decoder decodes a first address signal and selects one of the column lines. A second decoder decodes a second address signal, and generates a row output signal, with each row output signal of the second decoder having a corresponding row line.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: September 23, 1997
    Inventor: Ronald Loh-Hwa Yin
  • Patent number: 5646897
    Abstract: A logic circuit is provided for a memory device which can be operated at a high speed with a lower voltage power source level than conventional devices. This logic circuit can be used in a multi-bit test circuit executing the wired-OR-logic operation of complementary logic signals from a plurality of pre-sense amplifiers, receiving the output of the wired-OR-logic operation by an emitter follower using a bipolar transistor, and outputting an AND signal of the complementary logic signals by a level comparing circuit. A sense amplifier is also provided for executing the wired-OR-logic operation of complementary logic signals from a plurality of pre-sense amplifiers, raising the level of the output of the wired-OR-logic operation by a level shift circuit having a semiconductor element for applying an inverse bias potential to an input signal, executing the wired-OR-operation of the shifted up output and outputs from other blocks, and receiving and amplifying the output of the wired-OR-logic operation.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: July 8, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Seigou Yukutake, Masahiro Iwamura, Kinya Mitsumoto, Takashi Akioka, Noboru Akiyama
  • Patent number: 5646884
    Abstract: A data storage device consisting of at least two series connected resonant tunneling diodes (RTD1, RTD2) with capacitors (C1 ,C2) coupled thereacross. By coupling a time varying voltage V(t) across the series connected diodes, one the diodes can be selectively switched from a state below its peak current to a stable point above its peak current. The diode which switches state is controlled by the slope of the time varying voltage V(t). Cells consisting of at least two or more resonant tunneling diodes may be connected in series and can store up to 2.sup.N binary states where N is the number of resonant tunneling diodes in the cell.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: July 8, 1997
    Assignee: Texas Instruments Incorporated
    Inventor: Jan Paul Antoni van der Wagt
  • Patent number: 5600590
    Abstract: A process for the manufacture of an integrated voltage limiter and stabilizer component in a flash EEPROM memory device comprises a step of formation of an N type lightly doped well on a single-crystal silicon substrate; a step of formation of an active area on the surface of said N type well; a step of growth of a thin gate oxide layer over said active area; a step of implantation of a first heavy dose of N type dopant into said N type well to obtain an N type region; a step of implantation of a second heavy dose, higher than said first heavy dose, of N type dopant into said N type region to obtain an N+contact region to both the N type well and said N type region; a step of implantation of a third heavy dose, higher than said first heavy dose, of P type dopant into said N type region to form a P+ region.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: February 4, 1997
    Assignee: SGS-Thomson Microelectronics, S.r.l.
    Inventors: Paolo Ghezzi, Alfonso Maurelli
  • Patent number: 5587944
    Abstract: A high density multistate SRAM cell including N negative differential resistance diodes connected in series and to a load. The diodes and the load defining a memory node having N+1 stable states. A write transistor having a drain connected to the memory node and adapted to receive N+1 different amplitudes of voltage on the source, and a write signal on the gate. An amplifier having an input terminal connected to the memory node, and a read switch having an input terminal connected to the output terminal of the amplifier. A plurality of cells connected into a matrix with N+1 sense amplifiers associated with each column of the matrix so as to provide an output for each of the N+1 different amplitudes.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: December 24, 1996
    Assignee: Motorola
    Inventors: Jun Shen, Herbert Goronkin
  • Patent number: 5572472
    Abstract: A "zener-zap" memory cell with pretest capability for testing effects that would be realized from permanently programming the memory cell is provided. The memory cell is addressable and provides a binary signal at an output. The memory cell uses a zener diode as a memory element which is permanently programmed when selectively coupled to a programming voltage which exceeds the reverse breakdown voltage of the zener diode. The memory cell has a test circuit for generating the programmed binary signal at the output of the memory cell prior to permanently programming the zener diode and when coupled to a pretest voltage.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: November 5, 1996
    Assignee: Delco Electronics Corporation
    Inventors: Mark B. Kearney, Dennis M. Koglin, Douglas B. Osborn, William P. Whitlock
  • Patent number: 5535156
    Abstract: A transistorless memory cell for storing information as one of two possible bistable current states comprises (i) at least one first transistorless device exhibiting N-type negative differential resistance, including a high-impedance region, a low-impedance region and a negative-resistance region and having a polarity and (ii) at least one second transistorless device exhibiting an exponential or linear current-voltage characteristic and coupled to the first transistorless device. The second transistorless device may be a diode or a resistor. The read/write operation of the transistorless memory cell is performed in a current mode.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: July 9, 1996
    Assignee: California Institute of Technology
    Inventors: Harold J. Levy, Thomas C. McGill
  • Patent number: 5497345
    Abstract: To protect the thin tunnel oxide layer interposed between the floating gate region of memory cells and the substrate and which are subject to in-process damage, when the wafer is subjected to radiation, provision is made for a diode, connected between the control gate region of the cells and the substrate. The diode defines a conductive path that, when normal operating voltage is applied to the control gate regions, is turned off and has no effect on normal operation of the memory, and which is turned on to permit the passage of charges between the control gate region and the substrate, when the control gate potential exceeds normal operating potential but is less than the breakdown voltage of the tunnel oxide divided by the coupling factor of the control and floating gate regions of the cells. The diode is appropriately formed prior to patterning the control gate regions of the cells.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: March 5, 1996
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventor: Paolo G. Cappelletti
  • Patent number: 5483482
    Abstract: A semiconductor memory device comprises a plurality of memory cells each including an element with a potential barrier serving as a switching element and a capacitor one terminal of which is connected to the switching element. The memory cells are disposed in a matrix arrangement. Terminals of the respective capacitors which are not connected to the switching elements are connected to each other in intersection with bit lines in the memory cell arrangement to thereby form word lines. Alternatively, the terminals of the respective capacitors connected to the switching elements may be connected to each other in intersection with the bit lines to thereby form word lines.
    Type: Grant
    Filed: March 17, 1992
    Date of Patent: January 9, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Yamada, Yohji Watanabe
  • Patent number: 5473576
    Abstract: A column selector of a dynamic random access memory device is implemented by a plurality of switching circuits for transferring a potential difference from a sense amplifier to a shared data line pair, and one of the switching circuits selectively discharge the data lines of the pair to a ground voltage line for transferring the potential difference to the shared data line pair, wherein a potential control circuit is coupled between the switching circuits and the ground voltage line for decreasing the current flowing from the data line to the ground voltage line after production of an output data signal, thereby decreasing the current consumption.
    Type: Grant
    Filed: July 27, 1994
    Date of Patent: December 5, 1995
    Assignee: NEC Corporation
    Inventor: Yoshinori Matsui
  • Patent number: 5471087
    Abstract: A memory is formed from an array of switchless integrated circuit memory cells in a high-density configuration. These cells comprise a capacitor and two diodes in a configuration where one diode is used to charge one pole of the capacitor, and the other diode is used to discharge it from that same pole, over separate paired lines used respectively for charging and discharging, as well as reading. The other pole of the capacitor is tied to a single line used for both charging and discharging, and in support of reading. Drive and sense circuitry located at the periphery of the cell array is used to perform interconnect switching functions while writing or reading charges on cells in the array. Alternative high-density switched cell variations are also described. The cell arrays are fabricated on monolithic integrated circuits which are interconnected with one another by using a method which deposits and etches conductive material which links conductive traces between the monolithic dice.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: November 28, 1995
    Inventor: Walter R. Buerger, Jr.
  • Patent number: 5440148
    Abstract: A quantum operational device includes a plurality of quantum boxes arranged in a plurality of stages isolated by a distance which permits tunnelling of electrons or holes through the distance, uses as bit information the presence or absence of an electron or a hole in each of the quantum boxes, and prohibits tunnelling of an electron or a hole from a quantum box in a stage to another quantum box in an adjacent stage when an electron or a hole exists in the quantum box in the adjacent stage. The device only needs quite low power, performs operation at a high speed, and can be fabricated by a simple manufacturing process.
    Type: Grant
    Filed: April 18, 1994
    Date of Patent: August 8, 1995
    Assignee: Sony Corporation
    Inventor: Kazumasa Nomoto
  • Patent number: 5438539
    Abstract: A memory device includes a first address signal line, a pair of second address signal lines, a standby signal line, and a memory cell provided at a cross point at which the first address signal line crosses the pair of second address signal lines. The memory cell includes first and second elements connected, via a connection node, in series between the pair of second address signal lines in a forward direction, each of the first and second elements having a negative-differential conductance characteristic. A threshold diode is connected between the first address signal line and the connection node, and has a characteristic in which a current flows in the threshold diode when a voltage applied across the threshold diode exceeds threshold voltages. A gate is connected to the standby signal line and controls currents flowing in the first and second elements.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: August 1, 1995
    Assignee: Fujitsu Limited
    Inventor: Toshihiko Mori
  • Patent number: 5412614
    Abstract: An electronic matrix array device such as a data store, e.g. a datacard, or an electro-optic active matrix display, has crossing sets of row and column conductors and matrix elements such as memory or picture cells at the crossing intersections. At least some of the matrix elements include a two-terminal thin film non-linear impedance element which may be bi-directional, such as a MIM, or unidirectional, such as a diode. The array device also includes a row address decoder for addressing the row conductors and a column address decoder for addressing the column conductors, either or both decoders having respective stages for respective conductors of the relevant set of conductors.
    Type: Grant
    Filed: August 11, 1992
    Date of Patent: May 2, 1995
    Assignee: U.S. Philips Corporation
    Inventor: Neil C. Bird
  • Patent number: 5399879
    Abstract: An optical switching device is comprised of an asymmetrical double barrier resonant tunnelling diode (RTD) connected in series with load resistance apparatus to a power source, apparatus for illuminating the RTD with an infrared incident light beam, apparatus for applying signal power to the RTD, and apparatus for varying the power within the RTD.
    Type: Grant
    Filed: February 5, 1993
    Date of Patent: March 21, 1995
    Assignee: National Research Council of Canada
    Inventor: Hui C. Liu
  • Patent number: 5390145
    Abstract: A semiconductor memory device including a plurality of bit lines and a plurality of word lines which intersect to form a matrix of cross points. A respective memory cell is disposed at each cross point and corresponds to the respective word line and respective bit line intersecting at the respective cross point. Each memory cell includes a transfer gate having a first current terminal connected to the corresponding bit line and a control terminal connected to the corresponding word line. Each memory cell also includes a pair of serially connected negative differential resistance memory elements having an interconnection node therebetween. The interconnection node is connected to the second current terminal of the transfer gate.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: February 14, 1995
    Assignee: Fujitsu Limited
    Inventors: Yasuhiro Nakasha, Yuu Watanabe
  • Patent number: 5361225
    Abstract: A nonvolatile memory device having a field effect transistor for storing, which includes source and drain regions in a semiconductor substrate with a channel region interposed between them and a gate electrode above the channel region with a ferroelectric gate film sandwiched between them. Barrier metal is formed in contact with the source region of the field effect transistor for storing to make a Schottky diode in serial connection with the field effect transistor for storing. In reading information, voltage is applied to a serial circuit consisting of the field effect transistor for storing and the Schottky diode to turn the Schottky diode on.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: November 1, 1994
    Assignee: Rohm Co., Ltd.
    Inventor: Takanori Ozawa
  • Patent number: 5341325
    Abstract: A plurality of memory cells are constituted by a large number of belt-like first conductive members, a ferroelectric thin film formed on the first conductive members, and a large number of belt-like second conductive members formed on the film in a direction perpendicular to the first conductive members. A reading/writing section performs a reading/writing operation with respect to each memory cell after applying a predetermined voltage to at least memory cells other than a target memory cell to cause ferroelectric polarization corresponding to crosstalk components. A two-terminal switch integrally stacked on each of the memory cells serves to reduce dielectric polarization for the elimination of crosstalk caused in each memory cell.
    Type: Grant
    Filed: November 5, 1992
    Date of Patent: August 23, 1994
    Assignee: Olympus Optical Co., Ltd.
    Inventors: Hiroshi Nakano, Yasuo Isono
  • Patent number: 5313087
    Abstract: A polysilicon layer is provided with a p-type impurity, and masked with an oxide mask to define a p-type region of the polysilicon layer. A second impurity is then provided into first unmasked regions of the polysilicon layer. A second oxide mask is deposited and anisotropically etched to form spacers adjacent to the first oxide mask. The spacers define two diffusion barrier regions of the polysilicon layer adjacent to the p-type region. An n-type impurity is then provided into second unmasked regions of the polysilicon layer to form two n-type regions adjacent the diffusion barrier regions. The diffusion barrier regions prevent cross diffusion of the p-type and the n-type impurities within the polysilicon layer, while also being of sufficient dimensions to permit normal p/n operations.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: May 17, 1994
    Assignee: Micron Technology, Inc.
    Inventors: Hiang C. Chan, Pierre C. Fazan, Bohr-Winn Shih
  • Patent number: 5280445
    Abstract: A number of resonant tunneling diodes are connected in series with a resistor, a current source or a load device. A bit line is connected to every joint between any two devices through a switch. When properly biased, there can be (N+1).sup.m number of stable quantized operating points which are represented by a combination of m variables (of either voltage or current, where N is the number of peaks of the folding I-V characteristic and m is the number of bit lines. The m bit lines can write in (N+1).sup.m different combinations of inputs. During reading, the quantized voltage (or current) at each bit line is sensed. The number of stable states can be doubled by changing the polarity of the power supply.
    Type: Grant
    Filed: September 3, 1992
    Date of Patent: January 18, 1994
    Assignee: University of Maryland
    Inventors: Ming-Huei Shieh, Hung C. Lin
  • Patent number: 5267192
    Abstract: A semiconductor memory device having a plurality of memory cells, each memory cell having two nodes, an electric potential of each node designates a stored data, comprises: a word line; a pair of bit lines; a pair of field effect transistors (FETs) connected between the word line and the nodes; a pair of diodes connected between the bit lines and the nodes; a pair of load means connected between the nodes and a first potential; and an inverter connected to the word line for driving the FETs, wherein the electrical potential of the nodes are read out by the change of the potential of the word line controlled by the inverter.
    Type: Grant
    Filed: August 30, 1991
    Date of Patent: November 30, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kazutaka Nogami
  • Patent number: 5267193
    Abstract: A memory cell for multi-valued logic utilizing bidirectional folding V-I characteristics. Two devices with bidirectional multiple folding characteristics, such as the V-I characteristics of resonant tunneling diodes, are connected in series across a power supply. Multiple stable operating points are established where the positive resistance portions the folding characteristics interesect and can be used to store multiple levels of signal. With bidirectional folding characteristics, the number of operating points can be doubled by using both a positive power supply and a negative power supply. The signal can be written in and read out at the connecting point of the two devices.
    Type: Grant
    Filed: April 21, 1992
    Date of Patent: November 30, 1993
    Assignee: University of Maryland
    Inventor: Hung C. Lin
  • Patent number: 5257224
    Abstract: A plurality of strip shaped first polysilicon layers 3 are formed on a monocrystalline silicon substrate 1, a plurality of strip shaped second polysilicon layers 5 are formed thereon crossing the first polysilicon layers 3, and a plurality of strip shaped third polysilicon layers 8 are further formed thereon crossing the second polysilicon layers 5. The first and second polysilicon layers 3 and 5 are laser-annealed and monocrystallined. Contact holes 4 and 7 are selectively formed at the crossing points of the first polysilicon layers 3 and the second polysilicon layers 5, and the crossing points of the second polysilicon layers 5 and the third polysilicon layers 8. A PN junction is formed on each surface layer of the first polysilicon layers 3 and the second polysilicon layers 5 in the portions corresponding to these contact holes 4 and 7. Two layers of memory cell arrays using diode elements as memory cells are piled upon each other.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: October 26, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Isao Nojiri, Masahide Kaneko
  • Patent number: 5237674
    Abstract: A self-identifying scheme which permits a variety of integrated circuit semiconductor memory modules to inform a host processor as to each individual memory accessing speed or accessing time. Pre-encoded circuits within each memory module generate a coded signal when that module is selected by the host processor. The coded signal identifies the type of memory accessed, permitting the host processor to transfer information at a rate determined by the memory accessed.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: August 17, 1993
    Assignee: Apple Computer, Inc.
    Inventors: Rodger Mohme, Jerome Okun, R. Steven Smith, Michael De La Cruz
  • Patent number: 5191550
    Abstract: A semiconductor memory device employing a plurality of antifuse memory elements is disclosed. The memory elements have selected connection portions of two or more elements formed as a unit and are otherwise electrically connected for use without regard to the polarity of the applied voltage. Such two-way antifuse memory elements formed in parallel become a unit thereby reducing occupied area and enhancing device integration.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: March 2, 1993
    Assignee: Seiko Epson Corporation
    Inventor: Hideko Kubota
  • Patent number: 5128894
    Abstract: A memory cell for multi-value logic. Two devices with multiple peak folding characteristics, such as the V-I characteristics of resonant tunneling diodes, are connected in series across a power supply. Multiple stable operating points are established where the positive resistance portions of the respective folding voltage-current characteristics intersect and correspond to multiple quantized levels for storing information, creating a multi-valued memory cell.
    Type: Grant
    Filed: September 28, 1990
    Date of Patent: July 7, 1992
    Assignee: University of Maryland
    Inventor: Hung C. Lin