Patents Examined by Anh Phung
  • Patent number: 8174890
    Abstract: A memory cell array has plural memory strings arranged therein, each of which including a plurality of electrically-rewritable memory transistors and selection transistors. Each memory string includes a body semiconductor layer including four or more columnar portions, and a joining portion formed to join the lower ends thereof. An electric charge storage layer is formed to surround a side surface of the columnar portions. A first conductive layer is formed to surround a side surface of the columnar portions as well as the electric charge storage layer. A plurality of second conductive layers are formed on side surfaces of the joining portion via an insulation film, and function as control electrodes of a plurality of back-gate transistors formed at a respective one of the joining portions.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: May 8, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Maeda, Tsuneo Inaba
  • Patent number: 8174906
    Abstract: A method of programming a nonvolatile memory device according to the present invention includes precharging bit lines according to data loaded in page buffers; electrically connecting the precharged bit lines to channels corresponding to the bit lines, respectively, to charge the channels; and applying a word line voltage for a program after charging the channels. A channel voltage boosting of each of the channels is determined according to data loaded in adjacent page buffers.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: May 8, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ohsuk Kwon, Kihwan Choi
  • Patent number: 8169845
    Abstract: Some embodiments include apparatus and methods having a sense amplifier unit, a supply node to receive a supply voltage, and a line coupled to a memory cell of a device. The sense amplifier unit includes a circuit path coupled between the supply node and the line to carry a current having a value based on a value of information stored in the memory cell; and a second circuit including a second circuit path coupled between the supply node and the line to charge the line during the memory operation. Additional embodiments are disclosed.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: May 1, 2012
    Assignee: Atmel Corporation
    Inventor: Jimmy Fort
  • Patent number: 8164968
    Abstract: A voltage down converter (VDC) applicable to high-speed memory devices. The VDC includes a steady driver and active driver along with at least one additional transistor. The steady driver and active driver are coupled by a transistor switch during device start-up to provide fast ramp-up to operating voltage and current. After start-up, the steady driver and active drive function to maintain a steady operating voltage and current. An additional transistor is digitally controlled to drive up operating voltage and current upon issuance of an active command representing read, write, and/or refresh of memory. In this manner, the additional transistor provides fast compensation for fluctuations in operating voltage and current brought on by activity in the memory array.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: April 24, 2012
    Assignee: MOSAID Technologies Incorporated
    Inventors: Hong Beom Pyeon, Bruce Millar
  • Patent number: 8159859
    Abstract: A semiconductor storage device includes: a memory cell array including memory cells, each of the memory cells having a variable resistance element; and a control circuit configured to apply a control voltage, which is necessary for the variable resistance element to transit a resistance state, to a selected memory cell. When applying the control voltage plural times, the control circuit operates to set a value of the control voltage applied in a first control voltage application operation to be substantially equal to a minimum value of distribution of the voltage values of all the memory cells in the memory cell array required to transit the resistance state of the variable resistance element from a high resistance state to a low resistance state. The control circuit operates to perform a plurality of control voltage application operations by increasing the value of the control voltage by a certain value.
    Type: Grant
    Filed: March 9, 2010
    Date of Patent: April 17, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroshi Maejima
  • Patent number: 8154069
    Abstract: A nonvolatile semiconductor memory includes a memory cell string having a plurality of memory cell transistors connected in series, a selection gate transistor connected in series with one end of the memory cell string, and having a gate electrode provided on a gate insulating film on a semiconductor substrate, and an element isolation insulating layer which is provided in the semiconductor substrate. The gate electrode includes a first gate electrode provided on the gate insulating film, a first and second insulating films provided on the first gate electrode, and a second gate electrode provided on the second insulating film and the element isolation insulating layer, and electrically connected to the first gate electrode. An first upper surface portion of the element isolation insulating layer below the second gate electrode is leveled with an upper surface of the first gate electrode.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Mutsuo Morikado
  • Patent number: 8154908
    Abstract: A nonvolatile semiconductor storage device includes: a first wire and a second wire intersecting each other; a memory cell which is disposed at each intersection of the first wire and the second wire and electrically rewritable and in which a variable resistor for memorizing a resistance value as data in a nonvolatile manner and a rectifying device are connected in series; and a control circuit which applies a voltage necessary for writing of data to the first and second wires.
    Type: Grant
    Filed: February 10, 2011
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Maejima, Katsuaki Isobe, Hideo Mukai
  • Patent number: 8154934
    Abstract: A semiconductor memory device is disclosed. The semiconductor device includes a memory cell array, a clock signal generator configured to receive an external clock signal from the outside of the memory device and output an internal clock signal, and a data output unit configured to receive an internal data signal from the memory cell array and output a read data signal in response to the internal clock signal. The semiconductor memory device also includes a read data strobe unit configured to output a read data strobe signal having a cycle time of n times (n is an integer equal to or more than 2) a cycle time of the internal clock signal, based on the internal clock signal.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: April 10, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-Young Kim, Ho-Cheol Lee, Jung-Bae Lee
  • Patent number: 8154070
    Abstract: A nonvolatile memory includes a semiconductor substrate having a body member and a step member formed on the body member, a highly doped first well layer formed on the step member, a control electrode formed on the step member, a first and a second diffusion layers in the substrate, lightly doped second well layers formed on the main surface of the substrate between the first or the second diffusion layer and the first well layer, and a first and a second charge-storage multi-layers sandwiching the step member and the control electrode, each of the first and the second charge-storage multi-layers including a bottom oxide layer, a charge-storage film, a top oxide layer and a floating electrode which are formed in that order.
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: April 10, 2012
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Toshikazu Mizukoshi
  • Patent number: 8154911
    Abstract: A memory device includes bitlines, wordlines and a matrix of memory cells arranged in rows and columns. Each of the bitlines is electrically connected to memory cells in one of the columns. Each of the wordlines is electrically connected to memory cells in one of the rows. A bitline write voltage is applied to a first bitline. A wordline voltage is applied to a first wordline for writing data to a first memory cell connected to the first wordline and the first bitline. The first bitline and the second bitline are electrically connected for charge sharing between the first bitline and the second bitline. A predetermined time after electrically connecting the first bitline and the second bitline, the first and the second bitline are electrically disconnected and the bitline write voltage is applied to the second bitline. The wordline voltage is applied to a second wordline for writing data to a second memory cell connected to the second wordline and the second bitline.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: April 10, 2012
    Assignee: STMicroelectronics Pvt. Ltd.
    Inventors: Naveen Batra, Rajiv Kumar, Saurabh Agrawal
  • Patent number: 8154085
    Abstract: A nonvolatile semiconductor memory includes memory cell transistors and resistors. Each memory cell transistor has source/drain diffusion layers provided in a semiconductor substrate, a first gate insulating film located between the source/drain diffusion layers, a floating gate electrode layer located on the first gate insulating film, a first inter-gate insulating film located on the floating gate electrode layer, a control gate electrode layer located on the first inter-gate insulating layer, and a first low-resistance layer located on the control gate electrode layer. Each resistor has a second gate insulating film located on the semiconductor substrate, a first electrode layer located on the second gate insulating film, a second inter-gate insulating film located on the first electrode layer, a second electrode layer located on the second inter-gate insulating film, a second low-resistance layer located on the second electrode layer, and a contact plug connected to the second low-resistance layer.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shigeru Ishibashi
  • Patent number: 8154004
    Abstract: This invention relates to MRAM technology and new variations on MRAM array architecture to incorporate certain advantages from both cross-point and 1T-1MTJ architectures. The fast read-time and higher signal-to-noise ratio of the 1T-1MTJ architecture and the higher packing density of the cross-point architecture are both exploited by combining certain characteristics of these layouts. A single access transistor 16 is used to read the multiple MRAM cells in a segment of a column, which can be stacked vertically above one another in a plurality of MRAM array layers arranged in a ā€œZā€ axis direction.
    Type: Grant
    Filed: November 6, 2009
    Date of Patent: April 10, 2012
    Assignee: Micron Technology, Inc.
    Inventors: Mirmajid Seyyedy, Glen Hush
  • Patent number: 8153447
    Abstract: A nonvolatile ferroelectric perpendicular electrode cell comprises a ferroelectric capacitor and a serial PN diode switch. The ferroelectric capacitor includes a word line perpendicular electrode as a first electrode and a storage perpendicular electrode as a second electrode apart at a predetermined interval from the word line perpendicular electrode to have a column type, where a ferroelectric material is filled in a space where the first electrode are separated from the second electrode. The serial PN diode switch, which is connected between a bit line and the ferroelectric capacitor, selectively switches a current direction between the bit line and the ferroelectric capacitor depending on voltage change between the bit line and the ferroelectric capacitor.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: April 10, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hee Bok Kang
  • Patent number: 8154904
    Abstract: A storage system and method for operating the storage system that uses reversible resistance-switching elements is described. Techniques are disclosed herein for varying programming conditions to account for different resistances that memory cells have. These techniques can program memory cells in fewer attempts, which can save time and/or power. Techniques are disclosed herein for achieving a high programming bandwidth while reducing the worst case current and/or power consumption. In one embodiment, a page mapping scheme is provided that programs multiple memory cells in parallel in a way that reduces the worst case current and/or power consumption.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: April 10, 2012
    Assignee: SanDisk 3D LLC
    Inventors: Deepak C. Sekar, Klaus Schuegraf, Roy Scheuerlein
  • Patent number: 8149641
    Abstract: An active cycle control circuit for a semiconductor memory apparatus is configured to precharge a word line corresponding to a read cycle, and activate a word line corresponding to a refresh request signal in response to the refresh request signal generated during the read cycle.
    Type: Grant
    Filed: March 26, 2009
    Date of Patent: April 3, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventor: Sang-Kwon Lee
  • Patent number: 8149609
    Abstract: A nonvolatile semiconductor memory device comprising: a memory cell array including memory cells each provided at individual intersection between a first wiring and a second wiring, the memory cell comprising a variable resistive element, and predetermined numbers of the memory cells sharing the same first wiring to configure a page; a first control circuit configured to select a page subjected to data-writing, and to supply a constant voltage to the first wiring belonging to the selected page; a writing-voltage generating circuit configured to generate plural kinds of writing voltages for programming a resistance of the variable resistive element to one of three or more values based on a write-in data specifying three or more values; and a second control circuit configured to select the page subjected to data-writing, and to supply the writing voltages to predetermined numbers of the respective second wirings belonging to the selected page.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: April 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hiroyuki Nagashima
  • Patent number: 8148780
    Abstract: Methods, devices, and systems are disclosed for a memory cell having a floating body. A memory cell may include a transistor over an insulation layer, the transistor including a source, and a drain. The memory cell may also include a floating body including a first region positioned between the source and the drain, a second region positioned remote from each of the source and drain, and a passage extending through the insulation layer and coupling the first region to the second region. Additionally, the memory cell may include a bias gate at least partially surrounding the second region and configured for operably coupling to a bias voltage. Furthermore, the memory cell may include a plurality of dielectric layers, wherein each outer vertical surface of the second region has a dielectric layer of the plurality adjacent thereto.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: April 3, 2012
    Assignee: Micron Technology, Inc.
    Inventors: Sanh D. Tang, Mike N. Nguyen
  • Patent number: 8148708
    Abstract: A resistive memory device includes a first conductive line on a substrate, a vertical selection diode comprising a nanowire or a nanotube and being arranged over the first conductive line, a resistive element including a resistive layer arranged over the vertical selection diode; and a second conductive line arranged over the resistive element.
    Type: Grant
    Filed: December 26, 2008
    Date of Patent: April 3, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventors: Yun-Taek Hwang, Yu-Jin Lee
  • Patent number: 8149628
    Abstract: A non-volatile memory device includes memory cells having a semiconductor substrate, a stack layer, and source and drain regions disposed below a surface of the substrate and separated by a channel region. The stack layer includes an insulating layer disposed on the channel region, a charge storage layer disposed on the insulating layer, a multi-layer tunneling dielectric structure on the charge storage layer, and a gate disposed on the multi-layer tunneling dielectric structure. A negative bias is supplied to the gate to inject electrons into the charge storage layer through the multi-layer tunneling dielectric structure by ?FN to tunneling so that the threshold voltage of the device is increased. A positive bias is supplied to the gate to inject holes into the charge storage layer through the multi-layer tunneling dielectric structure by +FN tunneling so that the threshold voltage of the device is decreased.
    Type: Grant
    Filed: November 10, 2008
    Date of Patent: April 3, 2012
    Assignee: Macronix International Co., Ltd.
    Inventors: Hang-Ting Lue, Erh-Kun Lai, Szu-Yu Wang
  • Patent number: 8143611
    Abstract: A phase-change memory element includes a perovskite layer formed by a material having a perovskite structure, and a phase-change recording material layer which is formed on the perovskite layer, and changes the phase to a crystal state or amorphous state when supplied with an electric current via the perovskite layer.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: March 27, 2012
    Assignee: Canon Anelva Corporation
    Inventors: Young-suk Choi, Koji Tsunekawa