Patents by Inventor Satoru Hanzawa

Satoru Hanzawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20120211718
    Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.
    Type: Application
    Filed: April 5, 2012
    Publication date: August 23, 2012
    Inventors: AKIO SHIMA, Yoshitaka Sasago, Masaharu Kinoshita, Toshiyuki Mine, Norikatsu Takaura, Takahiro Morikawa, Kenzo Kurotsuchi, Satoru Hanzawa
  • Patent number: 8248843
    Abstract: In a memory array MCA which includes memory cells MC each having a variable-resistance-based memory device RQ and a select transistor MQ, an object is to receive a fixed quantity of storage data for a short time, and to realize writing operation to the memory cell, with suppressed peak current. In order to achieve the object, the data bus occupation time in rewriting operation is shortened by using plural sense amplifiers and storing storage data temporarily, and plural programming circuits are provided and activated using the control signals with different phases. By the above, the phase change memory system with low current consumption can be realized, without causing degradation of the utilization ratio of the data bus.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: August 21, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Satoru Hanzawa, Yoshikazu Iida
  • Publication number: 20120155162
    Abstract: A semiconductor storage apparatus provides a large capacity phase-change memory possessing high speed operation, low electrical current, and high-reliability. During the period that a read-out start signal is activated in the memory region control circuit and the block of pairs of sense-latch and write driver is performing the verify read in the upper section memory region; the write enable signals in the memory region control circuit are activated and the block of pairs of sense-latch and write driver perform rewrite operation of the data in the lower section memory region. This type of operation allows cancelling out the time required for the verify read and the time required for the time-division write operation by performing the verify read in one memory region, while performing time-division rewrite in other memory region, to achieve both higher reliability rewrite operation along with suppressing the rewrite operation peak electrical current.
    Type: Application
    Filed: December 15, 2011
    Publication date: June 21, 2012
    Inventor: Satoru HANZAWA
  • Publication number: 20120137058
    Abstract: A high-speed large-capacity phase-change memory is achieved. A semiconductor device according to the present invention includes: a plurality of memory planes MP; a plurality of storage information register groups SDRBK paired with the plurality of memory planes; and a chip control circuit CPCTL. The plurality of memory planes include a plurality of memory cells. Also, the plurality of storage information register groups temporarily retain information to be stored in the plurality of memory planes. Further, the chip control circuit includes a register which temporarily stores a value indicating volume of the storage information, and a first storage information volume is smaller than a second storage information volume. When the first storage information volume is written, the plurality of memory planes and the plurality of storage information register groups are activated during a first period.
    Type: Application
    Filed: June 18, 2010
    Publication date: May 31, 2012
    Applicant: HITACHI, LTD.
    Inventor: Satoru Hanzawa
  • Publication number: 20120134203
    Abstract: In a phase change memory, when M bit (8 bits=1 byte) data is written, erase operation and program operation are performed in units of n bit (M>n) data. Further, when M bit data is written, program operation is performed in units of the n bit (M>n) data. Further, when M bit data is read from the memory cell, read operation is performed in units of the n bit (M>n) data. For example, when the data is written into to the phase change memory, the data is not overwritten but program is performed after once erasing the target memory cell. The data size for erasure and the data size for program are made equal. Erase and program operation are performed only for the demanded data size.
    Type: Application
    Filed: November 18, 2011
    Publication date: May 31, 2012
    Applicant: Hitachi, Ltd.
    Inventors: Seiji Miura, Satoru Hanzawa
  • Publication number: 20120135548
    Abstract: A highly reliable large capacity phase change memory module is realized. A semiconductor device according to the present invention includes a memory array having a structure in which a storage layer using a chalcogenide material and a memory cell constituted of a diode are stacked, and an initialization condition and a rewriting condition are changed in accordance with the layer where a selected memory cell is located. A current mirror circuit is selected in accordance with an operation, and at the same time, the initialization condition and the rewriting condition (here, reset condition) are changed in accordance with the operation by a control mechanism of the reset current in a voltage selection circuit and a current mirror circuit.
    Type: Application
    Filed: February 5, 2012
    Publication date: May 31, 2012
    Inventors: SATORU HANZAWA, Hitoshi Kume, Motoyasu Terao, Tomonori Sekiguchi, Makoto Saen
  • Patent number: 8179739
    Abstract: A technique capable of manufacturing a semiconductor device without posing contamination in a manufacturing apparatus regarding a phase change memory including a memory cell array formed of memory cells using a storage element (RE) by a variable resistor and a select transistor (CT). A buffer cell is arranged between a sense amplifier (SA) and a memory cell array (MCA) and between a word driver (WDB) and the memory cell array. The buffer cell is formed of the resistive storage element (RE) and the select transistor (CT) same as those of the memory cell. The resistive storage element in the memory cell is connected to a bit-line via a contact formed above the resistive storage element. Meanwhile, in the buffer cell, the contact is not formed above the resistive storage element, and a state of being covered with an insulator is kept upon processing the contact in the memory cell. By such a processing method, exposure and sublimation of a chalcogenide film used in the resistive storage element can be avoided.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: May 15, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Satoru Hanzawa, Fumihiko Nitta, Nozomu Matsuzaki, Toshihiro Tanaka
  • Patent number: 8169819
    Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.
    Type: Grant
    Filed: January 17, 2010
    Date of Patent: May 1, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Akio Shima, Yoshitaka Sasago, Masaharu Kinoshita, Toshiyuki Mine, Norikatsu Takaura, Takahiro Morikawa, Kenzo Kurotsuchi, Satoru Hanzawa
  • Publication number: 20120087178
    Abstract: Adverse effects of a parasitic resistance and a parasitic capacitance of a driver circuit to a memory cell causes problems of thermal disturbance to a not-selected cell, unevenness of application voltage, degradation of a memory element in reading. A capacitor (C) is provided above or beneath a memory cell (MC) that includes a memory element to which a current write memory information and a selection element connected to the memory element. A charge stored in this capacitor writes to the memory element.
    Type: Application
    Filed: October 11, 2011
    Publication date: April 12, 2012
    Inventors: Takao WATANABE, Satoru Hanzawa, Yoshitaka Sasago
  • Publication number: 20120075926
    Abstract: A phase change memory capable of highly reliable operations is provided. A semiconductor device has a memory array having a structure in which memory cells are stacked including memory layers using a chalcogenide material and diodes, and initialization conditions and write conditions are changed according to the layer in which a selected memory cell is positioned. The initialization conditions and write conditions (herein, reset conditions) are changed according to the operation by selecting a current mirror circuit according to the operation and by a control mechanism of a reset current in a voltage select circuit and the current mirror circuit.
    Type: Application
    Filed: December 6, 2011
    Publication date: March 29, 2012
    Inventors: Satoru HANZAWA, Hitoshi Kume
  • Patent number: 8130575
    Abstract: A highly reliable large capacity phase change memory module is realized. A semiconductor device according to the present invention includes a memory array having a structure in which a storage layer using a chalcogenide material and a memory cell constituted of a diode are stacked, and an initialization condition and a rewriting condition are changed in accordance with the layer where a selected memory cell is located. A current mirror circuit is selected in accordance with an operation, and at the same time, the initialization condition and the rewriting condition (here, reset condition) are changed in accordance with the operation by a control mechanism of the reset current in a voltage selection circuit and a current mirror circuit.
    Type: Grant
    Filed: August 11, 2011
    Date of Patent: March 6, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Hanzawa, Hitoshi Kume, Motoyasu Terao, Tomonori Sekiguchi, Makoto Saen
  • Patent number: 8132063
    Abstract: To realize a fast and highly reliable phase-change memory system of low power consumption, a semiconductor device includes: a memory device which includes a first memory array having a first area including a plurality of first memory cells and a second area including a plurality of second memory cells; a controller coupled to the memory device to issue a command to the memory device; and a condition table for storing a plurality of trial writing conditions. The controller performs trial writing in the plurality of second memory cells a plurality of times based on the plurality of trial writing conditions stored in the condition table, and determines writing conditions in the plurality of first memory cells based on a result of the trial writing. The memory device performs writing in the plurality of first memory cells based on the writing conditions instructed from the controller.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: March 6, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Motoyasu Terao, Satoru Hanzawa, Hitoshi Kume, Minoru Ogushi, Yoshitaka Sasago, Masaharu Kinoshita, Norikatsu Takaura
  • Patent number: 8094489
    Abstract: A phase change memory capable of highly reliable operations is provided. A semiconductor device has a memory array having a structure in which memory cells are stacked including memory layers using a chalcogenide material and diodes, and initialization conditions and write conditions are changed according to the layer in which a selected memory cell is positioned. The initialization conditions and write conditions (herein, reset conditions) are changed according to the operation by selecting a current mirror circuit according to the operation and by a control mechanism of a reset current in a voltage select circuit and the current mirror circuit.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: January 10, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Hanzawa, Hitoshi Kume
  • Publication number: 20110292722
    Abstract: A highly reliable large capacity phase change memory module is realized. A semiconductor device according to the present invention includes a memory array having a structure in which a storage layer using a chalcogcnidc material and a memory cell constituted of a diode are stacked, and an initialization condition and a rewriting condition are changed in accordance with the layer where a selected memory cell is located. A current mirror circuit is selected in accordance with an operation, and at the same time, the initialization condition and the rewriting condition (here, reset condition) are changed in accordance with the operation by a control mechanism of the reset current in a voltage selection circuit and a current mirror circuit.
    Type: Application
    Filed: August 11, 2011
    Publication date: December 1, 2011
    Inventors: SATORU HANZAWA, Hitoshi Kume, Motoyasu Terao, Tomonori Sekiguchi, Makoto Saen
  • Publication number: 20110283039
    Abstract: To realize a fast and highly reliable phase-change memory system of low power consumption, a semiconductor device includes: a memory device which includes a first memory array having a first area including a plurality of first memory cells and a second area including a plurality of second memory cells; a controller coupled to the memory device to issue a command to the memory device; and a condition table for storing a plurality of trial writing conditions. The controller performs trial writing in the plurality of second memory cells a plurality of times based on the plurality of trial writing conditions stored in the condition table, and determines writing conditions in the plurality of first memory cells based on a result of the trial writing. The memory device performs writing in the plurality of first memory cells based on the writing conditions instructed from the controller.
    Type: Application
    Filed: July 26, 2011
    Publication date: November 17, 2011
    Inventors: MOTOYASU TERAO, Satoru Hanzawa, Hitoshi Kume, Minoru Ogushi, Yoshitaka Sasago, Masaharu Kinoshita, Norikatsu Takaura
  • Publication number: 20110273927
    Abstract: A semiconductor device has multiple memory cell groups arranged at intersections between multiple word lines and multiple bit lines intersecting the word lines. The memory cell groups each have first and second memory cells connected in series. Each of the first and the second memory cells has a select transistor and a resistive storage device connected in parallel. The gate electrode of the select transistor in the first memory cell is connected with a first gate line, and the gate electrode of the select transistor in the second memory cell is connected to a second gate line. A first circuit block for driving the word lines (word driver group WDBK) is arranged between a second circuit block for driving the first and second gate lines (phase-change-type chain cell control circuit PCCCTL) and multiple memory cell groups (memory cell array MA).
    Type: Application
    Filed: May 9, 2011
    Publication date: November 10, 2011
    Inventors: Satoru Hanzawa, Yoshitska Sasago
  • Publication number: 20110242872
    Abstract: A highly-reliable, highly-integrated large-capacity phase-change memory is achieved. For this purpose, for example, memory tiles MT0, MT1 are provided respectively at points of intersection of global bit line GBL0 and global word lines GWL00B, GWL01B. Word lines WL000 of MT0, MT1 are commonly connected to an output from a word-line driving circuit WD0 which is controlled by GWL00B, and word lines WL001 of MT0, MT1 are commonly connected to an output from a word-line driving circuit WD1 controlled by GWL01B. For example, when WD0 is activated in accordance with a rewrite operation, an output from WD0 is connected to GBL0 via any one of four memory cells MC00, MC01 connected to WL000 of MT0, MT1.
    Type: Application
    Filed: December 7, 2009
    Publication date: October 6, 2011
    Applicant: HITACHI, LTD.
    Inventor: Satoru Hanzawa
  • Publication number: 20110216583
    Abstract: A phase change memory capable of highly reliable operations is provided. A semiconductor device has a memory array having a structure in which memory cells are stacked including memory layers using a chalcogenide material and diodes, and initialization conditions and write conditions are changed according to the layer in which a selected memory cell is positioned. The initialization conditions and write conditions (herein, reset conditions) are changed according to the operation by selecting a current mirror circuit according to the operation and by a control mechanism of a reset current in a voltage select circuit and the current mirror circuit.
    Type: Application
    Filed: May 20, 2011
    Publication date: September 8, 2011
    Inventors: Satoru HANZAWA, Hitoshi Kume
  • Publication number: 20110211390
    Abstract: A technique capable of manufacturing a semiconductor device without posing contamination in a manufacturing apparatus regarding a phase change memory including a memory cell array formed of memory cells using a storage element (RE) by a variable resistor and a select transistor (CT). A buffer cell is arranged between a sense amplifier (SA) and a memory cell array (MCA) and between a word driver (WDB) and the memory cell array. The buffer cell is formed of the resistive storage element (RE) and the select transistor (CT) same as those of the memory cell. The resistive storage element in the memory cell is connected to a bit-line via a contact formed above the resistive storage element. Meanwhile, in the buffer cell, the contact is not formed above the resistive storage element, and a state of being covered with an insulator is kept upon processing the contact in the memory cell. By such a processing method, exposure and sublimation of a chalcogenide film used in the resistive storage element can be avoided.
    Type: Application
    Filed: August 10, 2007
    Publication date: September 1, 2011
    Applicant: RENESAS TECHNOLOGY CROP.
    Inventors: Satoru Hanzawa, Fumihiko Nitta, Nozomu Matsuzaki, Toshihiro Tanaka
  • Patent number: 7996735
    Abstract: To realize a fast and highly reliable phase-change memory system of low power consumption, a semiconductor device includes: a memory device which includes a first memory array having a first area including a plurality of first memory cells and a second area including a plurality of second memory cells; a controller coupled to the memory device to issue a command to the memory device; and a condition table for storing a plurality of trial writing conditions. The controller performs trial writing in the plurality of second memory cells a plurality of times based on the plurality of trial writing conditions stored in the condition table, and determines writing conditions in the plurality of first memory cells based on a result of the trial writing. The memory device performs writing in the plurality of first memory cells based on the writing conditions instructed from the controller.
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: August 9, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Motoyasu Terao, Satoru Hanzawa, Hitoshi Kume, Minoru Ogushi, Yoshitaka Sasago, Masaharu Kinoshita, Norikatsu Takaura