Patents by Inventor Tsuyoshi Kawagoe

Tsuyoshi Kawagoe 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: 20230282618
    Abstract: A semiconductor device is provided with: a reference unit in which at least two circuit modules are stacked with circuit layers adjoining each other; an additional unit in which at least two other circuit modules are stacked with circuit layers adjoining each other, the additional unit being stacked on the reference unit; and a via disposed through the reference unit and the additional unit and extending in a stacking direction. The via includes a reference via disposed in the reference unit, and an additional via disposed in the additional unit. The additional via at the position of contact with the reference via has a diameter smaller than a diameter of the reference via.
    Type: Application
    Filed: July 16, 2020
    Publication date: September 7, 2023
    Inventors: Ichiro HOMMA, Tsuyoshi KAWAGOE
  • Publication number: 20130248809
    Abstract: As for a variable resistive element including first and second electrodes, and a variable resistor containing a metal oxide between the first and second electrodes, in a case where a current path having a locally high current density of a current flowing between the both electrodes is formed in the metal oxide, and resistivity of at least one specific electrode having higher resistivity of the both electrodes is 100 ??cm or more, a dimension of a contact region of the specific electrode with the variable resistor in a short side or short axis direction is set to be more than 1.4 times as long as a film thickness of the specific electrode, which reduces variation in parasitic resistance generated in an electrode part due to process variation of the electrode, and prevents variation in resistance change characteristics of the variable resistive element generated due to the variation in parasitic resistance.
    Type: Application
    Filed: March 22, 2013
    Publication date: September 26, 2013
    Applicants: ELPIDA MEMORY, INC., SHARP KABUSHIKI KAISHA
    Inventors: Yukio TAMAI, Takashi NAKANO, Nobuyoshi AWAYA, Kazuo AIZAWA, Isamu ASANO, Naoya HIGANO, Tsuyoshi KAWAGOE
  • Patent number: 8513638
    Abstract: A semiconductor device may include, but is not limited to: a first insulating film; a second insulating film over the first insulating film; a first memory structure between the first and second insulating films; and a third insulating film between the first and second insulating films. The first memory structure may include, but is not limited to: a heater electrode; and a phase-change memory element between the heater electrode and the second insulating film. The phase-change memory element contacts the heater electrode. The third insulating film covers at least a side surface of the phase-change memory element. Empty space is positioned adjacent to at least one of the heater electrode and the third insulating film.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: August 20, 2013
    Assignee: Elpida Memory, Inc.
    Inventors: Tomoyasu Kakegawa, Isamu Asano, Tsuyoshi Kawagoe, Hiromi Sasaoka, Naoya Higano, Yuta Watanabe
  • Publication number: 20120056148
    Abstract: A semiconductor device may include, but is not limited to: a first insulating film; a second insulating film over the first insulating film; a first memory structure between the first and second insulating films; and a third insulating film between the first and second insulating films. The first memory structure may include, but is not limited to: a heater electrode; and a phase-change memory element between the heater electrode and the second insulating film. The phase-change memory element contacts the heater electrode. The third insulating film covers at least a side surface of the phase-change memory element. Empty space is positioned adjacent to at least one of the heater electrode and the third insulating film.
    Type: Application
    Filed: September 2, 2011
    Publication date: March 8, 2012
    Applicant: ELPIDA MEMORY, INC.
    Inventors: Tomoyasu Kakegawa, Isamu Asano, Tsuyoshi Kawagoe, Hiromi Sasaoka, Naoya Higano, Yuta Watanabe
  • Publication number: 20100302842
    Abstract: A semiconductor memory device includes: first and second impurity diffusion layers that form a part of a semiconductor substrate, each of the impurity diffusion layers function as one and the other of an anode and a cathode, respectively of a pn-junction diode; a recording layer connected to the second impurity diffusion layer; and a cylindrical sidewall insulation film provided on the first impurity diffusion layer. At least a part of the second diffusion layer and at least a part of the recording layer are formed in a region surrounded by a sidewall insulation film. According to the present invention, because a pillar-shaped pn-junction diode and the recording layer are formed in a self-aligned manner, the degree of integration of a semiconductor memory device can be increased. Further, because a silicon pillar is a part of the semiconductor substrate, a leakage current attributable to a crystal defect can be reduced.
    Type: Application
    Filed: June 2, 2010
    Publication date: December 2, 2010
    Applicant: ELPIDA MEMORY, INC.
    Inventors: Tsuyoshi KAWAGOE, Isamu Asano
  • Patent number: 7696504
    Abstract: A phase change memory device comprises an insulating layer and a phase change layer formed on the insulating layer. A phase change layer has a pad portion. The pad portion is formed with at least one slit.
    Type: Grant
    Filed: September 19, 2007
    Date of Patent: April 13, 2010
    Assignee: Elpida Memory, Inc.
    Inventor: Tsuyoshi Kawagoe
  • Patent number: 7675770
    Abstract: A phase change memory device, comprising a phase change memory device; a semiconductor substrate; a MOS transistor disposed at each intersection of a plurality of word lines and a plurality of bit lines arranged in a matrix form; a plurality of phase change memory elements for storing data of a plurality of bits, each formed on an upper area opposite to a diffusion layer of the MOS transistor in a phase change layer made of phase change material; a lower electrode structure for electrically connecting each of the plurality of phase change memory elements to the diffusion layer of the MOS transistor.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: March 9, 2010
    Assignee: Elpida Memory, Inc.
    Inventors: Isamu Asano, Yukio Fuji, Kiyoshi Nakai, Tsuyoshi Kawagoe
  • Patent number: 7554147
    Abstract: A memory device in which both DRAM and phase-change memory (PCRAM) are mounted is provided with a DRAM bit line, a PCRAM bit line or a PCRAM source line formed on an conductive layer shared with the DRAM bit line, and a sense amplifier connected between the DRAM bit line and the PCRAM bit line. The memory device further has a capacitive element disposed on the upper layer of the DRAM bit line, and a phase-change element disposed on the upper layer of the PCRAM bit line. The lower electrode of the capacitive element and the lower electrode of the phase-change memory element are formed on the shared conductive layer.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: June 30, 2009
    Assignee: Elpida Memory, Inc.
    Inventors: Isamu Asano, Tsuyoshi Kawagoe, Kiyoshi Nakai, Yukio Fuji, Kazuhiko Kajigaya
  • Patent number: 7550756
    Abstract: In a semiconductor memory comprising a matrix of memory cells each composed of one transistor and one chalcogenide layer as a memory element, no chalcogenide layer is disposed at a joint between an upper electrode wire connected to the chalcogenide layer and another wiring layer.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: June 23, 2009
    Assignee: Elpida Memory, Inc.
    Inventors: Isamu Asano, Tsuyoshi Kawagoe
  • Patent number: 7502252
    Abstract: For the purpose of providing a phase change memory device advantageous in layout and operation control by obtaining sufficient write current for high integrated phase change memory devices, the nonvolatile semiconductor memory device of the invention in which word lines and bit lines are arranged in a matrix-shape comprises a select transistor formed at each cross point of the word lines and the bit lines, and a plurality of memory elements commonly connected to the select transistor at one end and connected to a different element select line at an other end and which is capable of writing and reading data. Write and read operations for the selected memory element are controlled by supplying a predetermined current through the select transistor and through the element select line connected to the selected memory element, and the element select lines are arranged in parallel with the bit lines.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: March 10, 2009
    Assignee: Elpida Memory Inc.
    Inventors: Yukio Fuji, Isamu Asano, Tsuyoshi Kawagoe, Kiyoshi Nakai
  • Patent number: 7449711
    Abstract: A phase-change memory device includes a plurality of bit lines extending in a row direction, a plurality of selection lines extending in a column direction, and an array of memory cells each disposed at one of intersections between the bit lines and selection lines. Each memory cell includes a chalcogenide element and a diode connected in series, and an n-type contact layer underlying the n-type layer of the diode. Adjacent two of memory cells share a common bit-line contact plug connecting the n-type contact layers and the bit line.
    Type: Grant
    Filed: January 11, 2006
    Date of Patent: November 11, 2008
    Assignee: Elpida Memory, Inc.
    Inventors: Isamu Asano, Tsuyoshi Kawagoe, Yukio Fuji, Kiyoshi Nakai, Kazuhiko Kajigaya
  • Publication number: 20080067488
    Abstract: A phase change memory device comprises an Insulating layer and a phase change layer formed on the insulating layer. The phase change layer has a plurality of linear portions. The linear portions extend in a first direction are spaced from each other in a second direction perpendicular to the first direction. The neighboring ones of the linear portions have ends which open.
    Type: Application
    Filed: September 19, 2007
    Publication date: March 20, 2008
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Tsuyoshi KAWAGOE
  • Publication number: 20080067487
    Abstract: A phase change memory device comprises an insulating layer and a phase change layer formed on the insulating layer. A phase change layer has a pad portion. The pad portion is formed with at least one slit.
    Type: Application
    Filed: September 19, 2007
    Publication date: March 20, 2008
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Tsuyoshi KAWAGOE
  • Publication number: 20080043522
    Abstract: For the purpose of providing a phase change memory device advantageous in layout and operation control by obtaining sufficient write current for high integrated phase change memory devices, the nonvolatile semiconductor memory device of the invention in which word lines and bit lines are arranged in a matrix-shape comprises a select transistor formed at each cross point of the word lines and the bit lines, and a plurality of memory elements commonly connected to the select transistor at one end and connected to a different element select line at an other end and which is capable of writing and reading data. Write and read operations for the selected memory element are controlled by supplying a predetermined current through the select transistor and through the element select line connected to the selected memory element, and the element select lines are arranged in parallel with the bit lines.
    Type: Application
    Filed: October 25, 2005
    Publication date: February 21, 2008
    Inventors: Yukio Fuji, Isamu Asano, Tsuyoshi Kawagoe, Kiyoshi Nakai
  • Publication number: 20070148896
    Abstract: A semiconductor device includes memory cells each having an MISFET for memory selection formed on one major surface of a semiconductor substrate and a capacitive element comprised of a lower electrode electrically connected at a bottom portion to one of a source and drain of the MISFET for memory selection via a first metal layer and an upper electrode formed on the lower electrode via a capacitive insulating film. The lower electrode has a thickness of 30 nm or greater at the bottom portion thereof. Sputtering with a high ionization ratio and high directivity, such as PCM, is adapted to the formation of the lower electrode to make only the bottom portion of a capacitor thicker.
    Type: Application
    Filed: November 27, 2006
    Publication date: June 28, 2007
    Inventors: Yoshitaka Nakamura, Hidekazu Goto, Isamu Asano, Mitsuhiro Horikawa, Keiji Kuroki, Hiroshi Sakuma, Kenichi Koyanagi, Tsuyoshi Kawagoe
  • Publication number: 20070141786
    Abstract: A method of manufacturing a non-volatile memory element in the present invention comprises a first step for forming an adhesion layer on an interlayer insulating film so that an electrical connection is established with a lower electrode, a second step for forming a recording layer containing a phase change material on the adhesion layer, a third step for forming an upper electrode that is electrically connected to the recording layer, and a fourth step for diffusing in the recording layer some of the adhesion layer positioned between at least the lower electrode and the recording layer.
    Type: Application
    Filed: December 12, 2006
    Publication date: June 21, 2007
    Inventors: Tsuyoshi Kawagoe, Isamu Asano
  • Patent number: 7224016
    Abstract: A semiconductor device includes memory cells each having an MISFET for memory selection formed on one major surface of a semiconductor substrate and a capacitive element comprised of a lower electrode electrically connected at a bottom portion to one of a source and drain of the MISFET for memory selection via a first metal layer and an upper electrode formed on the lower electrode via a capacitive insulating film. The lower electrode has a thickness of 30 nm or greater at the bottom portion thereof. Sputtering with a high ionization ratio and high directivity, such as PCM, is adapted to the formation of the lower electrode to make only the bottom portion of a capacitor thicker.
    Type: Grant
    Filed: February 13, 2004
    Date of Patent: May 29, 2007
    Assignees: Elpida Memory, Inc., Hitachi ULSI Systems, Co., Ltd., Hitachi Ltd.
    Inventors: Yoshitaka Nakamura, Hidekazu Goto, Isamu Asano, Mitsuhiro Horikawa, Keiji Kuroki, Hiroshi Sakuma, Kenichi Koyanagi, Tsuyoshi Kawagoe
  • Publication number: 20070090336
    Abstract: In a semiconductor memory comprising a matrix of memory cells each composed of one transistor and one chalcogenide layer as a memory element, no chalcogenide layer is disposed at a joint between an upper electrode wire connected to the chalcogenide layer and another wiring layer.
    Type: Application
    Filed: July 7, 2006
    Publication date: April 26, 2007
    Inventors: Isamu Asano, Tsuyoshi Kawagoe
  • Patent number: 7183170
    Abstract: After an upper electrode protective film is formed such that it is in a firm contact with ruthenium film of the upper electrode without damaging the ruthenium film, the upper electrode is etched, thereby, a MIM capacitor is obtained in which leak current is not increased due to oxidation of the ruthenium film of the upper electrode.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: February 27, 2007
    Assignee: Elpida Memory, Inc.
    Inventors: Yoshitaka Nakamura, Tsuyoshi Kawagoe, Hiroshi Sakuma, Isamu Asano, Keiji Kuroki, Hidekazu Goto, Shinpei Iijima
  • Patent number: 7141471
    Abstract: A sidewall insulating film (11) made of a silicon oxide film is formed on the sidewall of a gate electrode (7) (word line) with an aim to reduce the capacitance to the word line serving as the major component of the bit line capacitance. Also, when openings for connecting the bit lines are formed above the spaces of the gate electrodes (7) (word lines) by the dry etching of a silicon oxide film (31) above contact holes (12), a silicon nitride film (19) to be an etching stopper is provided below the silicon oxide film (31) so as to reduce the amount of the bottom surface of the opening receded below the upper surface of a cap insulating film (9).
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: November 28, 2006
    Assignee: Elpida Memory, Inc.
    Inventors: Satoru Yamada, Hiroyuki Enomoto, Nobuya Saito, Tsuyoshi Kawagoe, Hisaomi Yamashita