Patents by Inventor Yoshinori Kumura

Yoshinori Kumura 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: 20160043135
    Abstract: According to one embodiment, a semiconductor memory device including a memory cell array and peripheral region includes a magnetoresistive element provided in the memory cell array, first contact under the magnetoresistive element and second contact in the peripheral region. A material of the first contact differs from that of the second contact.
    Type: Application
    Filed: February 23, 2015
    Publication date: February 11, 2016
    Inventor: Yoshinori KUMURA
  • Publication number: 20160027843
    Abstract: According to one embodiment, a semiconductor memory device includes a magnetic tunnel junction (MTJ) element, a contact layer and a first material layer. The contact layer is provided under the MTJ element and comprises a first material. The first material layer is provided around the contact layer and comprises the first material or an oxide of the first material.
    Type: Application
    Filed: February 23, 2015
    Publication date: January 28, 2016
    Inventor: Yoshinori KUMURA
  • Publication number: 20150255707
    Abstract: According to one embodiment, a magnetic memory device includes a first electrode, a second electrode having magnetism and having a major surface facing a major surface of the first electrode, a third electrode having a major surface facing the major surface of the first electrode and located away from the second electrode, and a movable member having magnetism and located between the first and second electrodes and between the first and third electrodes, the movable member being able to be brought into contact with the first electrode and being able to be selectively brought into contact with one of the second and third electrodes.
    Type: Application
    Filed: July 15, 2014
    Publication date: September 10, 2015
    Inventor: Yoshinori KUMURA
  • Publication number: 20150179923
    Abstract: According to one embodiment, a magnetic memory is disclosed. The magnetic memory includes a substrate, and a contact plug provided on the substrate. The contact plug includes a first contact plug, and a second contact plug provided on the first contact plug and having a smaller diameter than that of the first contact plug. The magnetic memory further includes a magnetoresistive element provided on the second contact plug. The diameter of the second contact plug is smaller than that of the magnetoresistive element.
    Type: Application
    Filed: February 25, 2015
    Publication date: June 25, 2015
    Inventor: Yoshinori KUMURA
  • Patent number: 8987846
    Abstract: According to one embodiment, a magnetic memory is disclosed. The magnetic memory includes a substrate, and a contact plug provided on the substrate. The contact plug includes a first contact plug, and a second contact plug provided on the first contact plug and having a smaller diameter than that of the first contact plug. The magnetic memory further includes a magnetoresistive element provided on the second contact plug. The diameter of the second contact plug is smaller than that of the magnetoresistive element.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: March 24, 2015
    Inventor: Yoshinori Kumura
  • Publication number: 20150070981
    Abstract: According to one embodiment, a magnetoresistance element includes a spin valve structure portion formed on a substrate and a tunnel magnetic junction structure portion formed on a part of the spin valve structure portion. The spin valve structure portion is formed by having a nonmagnetic layer sandwiched between first and second ferromagnetic layers. Further, the tunnel magnetic junction structure portion includes the second ferromagnetic layer, a tunnel barrier layer formed on a part of the second ferromagnetic layer and a third ferromagnetic layer formed on the tunnel barrier layer.
    Type: Application
    Filed: January 21, 2014
    Publication date: March 12, 2015
    Inventor: Yoshinori KUMURA
  • Publication number: 20150070983
    Abstract: According to one embodiment, a magnetic memory device includes a bit line, a source line, a magnetoresistance effect element between the bit line and the source line, and a nonlinear element provided between the bit line and the source line and connected in series to the magnetoresistance effect element. The nonlinear element has a voltage-current characteristic in which current increases until a voltage to be applied becomes a predetermined applied voltage, when current flowing through the nonlinear element is within a range not exceeding a predetermined current, and current increases within an applied voltage range lower than the predetermined applied voltage, when current flowing through the nonlinear element is within a range exceeding the predetermined current.
    Type: Application
    Filed: March 10, 2014
    Publication date: March 12, 2015
    Inventor: Yoshinori KUMURA
  • Publication number: 20140284737
    Abstract: According to one embodiment, a magnetic memory is disclosed. The magnetic memory includes a substrate, and a contact plug provided on the substrate. The contact plug includes a first contact plug, and a second contact plug provided on the first contact plug and having a smaller diameter than that of the first contact plug. The magnetic memory further includes a magnetoresistive element provided on the second contact plug. The diameter of the second contact plug is smaller than that of the magnetoresistive element.
    Type: Application
    Filed: September 4, 2013
    Publication date: September 25, 2014
    Inventor: Yoshinori Kumura
  • Patent number: 8183610
    Abstract: According to an aspect of the present invention, there is provided a nonvolatile memory including: a cell transistor including: a gate electrode and first and second diffusion layers; a second insulating film covering the cell transistor; first and second plugs penetrating the second insulating film to reach the first and second diffusion layers, respectively; a ferroelectric capacitor having a ferroelectric film and first and second electrodes, the first electrode contacting with the first plug; a first conductive spacer contacting with the second plug and including the same material as the first electrode; a third insulating film covering side faces of the first electrode, the ferroelectric film and the first conductive spacer; and a first wiring that is continuously formed with the second electrode and connected to the first conductive spacer and that includes the same material as the second electrode.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: May 22, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoshinori Kumura
  • Publication number: 20100193849
    Abstract: According to one embodiment, a semiconductor memory device having a ferroelectric film, includes a semiconductor substrate, a field effect transistor formed on the semiconductor substrate, an inter-layer insulating film formed on the field effect transistor and the semiconductor substrate, a plug constituted with a single-crystalline structure, the plug being formed in the inter-layer insulating film and being connected with a source or a drain of the field effect transistor, a lower electrode constituted with a single-crystalline structure formed on the plug, a ferroelectric film formed on the lower electrode an upper electrode formed on the ferroelectric film.
    Type: Application
    Filed: January 18, 2010
    Publication date: August 5, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Jun NISHIMURA, Yoshinori KUMURA, Hiroyuki KANAYA, Tohru OZAKI
  • Patent number: 7763920
    Abstract: According to an aspect of the present invention, there is provided a semiconductor memory including a lower electrode, a first insulating region formed in the same layer as the lower electrode, a ferroelectric film formed on the lower electrode and on the first insulating region, an upper electrode formed on the ferroelectric film, a second insulating region formed in the same layer as the upper electrode and a transistor. The first insulating region partitions the lower electrode. The second insulating region partitions the upper electrode. The transistor includes a first impurity region connected to the lower electrode and a second impurity region connected to the upper electrode. At least one of the first insulating region and the second insulating region is formed by insulating the lower electrode or the upper electrode.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: July 27, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Kumura, Tohru Ozaki, Iwao Kunishima
  • Publication number: 20100129938
    Abstract: A semiconductor device includes: a semiconductor substrate and a transistor formed on the semiconductor substrate. The semiconductor device also includes: a first interlayer insulation film formed on the semiconductor substrate including the upper portion of the transistor, a first contact formed to be connected through the first interlayer insulation film to the transistor, a ferroelectric capacitor formed to be connected to the first contact, a second interlayer insulation film formed on the first interlayer insulation film, and a second contact formed to connect the ferroelectric capacitor to a wiring through the second interlayer insulation film. The contact surfaces between the second contact and the ferroelectric capacitor have the same planar shape.
    Type: Application
    Filed: January 25, 2010
    Publication date: May 27, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshinori Kumura, Yoshiro Shimojo
  • Publication number: 20100117127
    Abstract: A semiconductor storage device includes a memory cell having a ferroelectric capacitor and a cell transistor connected in parallel. The memory cell includes: a first conductive layer provided above a substrate; a ferroelectric layer formed on a top surface of the first conductive layer; a second conductive layer formed on a top surface of the ferroelectric layer; and a stopper layer formed in the same layer as the ferroelectric layer. A selection ratio of the stopper layer under CMP is higher than that of the ferroelectric layer under CMP.
    Type: Application
    Filed: September 18, 2009
    Publication date: May 13, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yoshinori KUMURA
  • Publication number: 20100117128
    Abstract: A semiconductor memory device has a semiconductor substrate, an impurity diffusion layer that is formed at a surface portion of the semiconductor substrate, an interlayer insulating film that is formed on the semiconductor substrate, a contact plug that penetrates the interlayer insulating film, has a top surface formed higher than a top surface of the interlayer insulating film, a region having a convex shape formed higher than the top surface of the interlayer insulating film, and contacts the impurity diffusion layer, a lower capacitor electrode film that is formed on the contact plug and a predetermined region of the interlayer insulating film, a ferroelectric film that is formed on the lower capacitor electrode film, and an upper capacitor electrode film that is formed on the ferroelectric film.
    Type: Application
    Filed: September 22, 2009
    Publication date: May 13, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Saku Hashiura, Yoshinori Kumura, Tohru Ozaki
  • Publication number: 20100072525
    Abstract: According to a method for manufacturing a semiconductor memory device of the present invention, a capacitor lower electrode film is left on the wiring layer located above a dummy transistor. In this manner, when processing of the capacitors is performed by removing a capacitor upper electrode film and a ferroelectric film, removal of the wiring layer can be prevented, and the connection between the diffusion layer of a select transistor and a bit line can be secured.
    Type: Application
    Filed: September 3, 2009
    Publication date: March 25, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiro Shimojo, Tohru Ozaki, Yoshinori Kumura
  • Publication number: 20100072526
    Abstract: A semiconductor memory device includes a semiconductor substrate; a ferroelectric capacitor comprising an upper electrode, a ferroelectric film, and a lower electrode above the semiconductor substrate; and an upper interlayer dielectric film surrounding a periphery of the ferroelectric capacitor, wherein a gap is provided between the ferroelectric capacitor and the upper interlayer dielectric film.
    Type: Application
    Filed: September 4, 2009
    Publication date: March 25, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshinori Kumura, Hiroyuki Kanaya
  • Publication number: 20100052022
    Abstract: According to an aspect of the present invention, there is provided a nonvolatile memory including: a cell transistor including: a gate electrode and first and second diffusion layers; a second insulating film covering the cell transistor; first and second plugs penetrating the second insulating film to reach the first and second diffusion layers, respectively; a ferroelectric capacitor having a ferroelectric film and first and second electrodes, the first electrode contacting with the first plug; a first conductive spacer contacting with the second plug and including the same material as the first electrode; a third insulating film covering side faces of the first electrode, the ferroelectric film and the first conductive spacer; and a first wiring that is continuously formed with the second electrode and connected to the first conductive spacer and that includes the same material as the second electrode.
    Type: Application
    Filed: August 27, 2009
    Publication date: March 4, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yoshinori Kumura
  • Publication number: 20100012994
    Abstract: A semiconductor storage device has the ferroelectric capacitor has: a capacitor film formed above the MOS transistor with an interlayer insulating film interposed therebetween; a first capacitor electrode electrically connected to a source region of the MOS transistor and formed in contact with one side wall of the capacitor film; and a second capacitor electrode electrically connected to a drain region of the MOS transistor and formed in contact with the other side wall of the capacitor film, and the capacitor film is composed of a film stack including a plurality of films including a first insulating film intended to orient a film formed on an upper surface thereof in a predetermined direction and a ferroelectric film formed on the first insulating film to be oriented in a direction perpendicular to the semiconductor substrate.
    Type: Application
    Filed: July 16, 2009
    Publication date: January 21, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tohru OZAKI, Iwao KUNISHIMA, Yoshinori KUMURA
  • Patent number: 7612398
    Abstract: A semiconductor storage device wherein a plurality of ferroelectric capacitors are sufficiently covered with a hydrogen barrier film formed thereon comprises a field effect transistor formed on one surface side of a semiconductor substrate, a plurality of ferroelectric capacitors formed close to each other above the field effect transistor, an insulting film configured to cover the plurality of ferroelectric capacitors and planarised a space between adjacent ferroelectric capacitors in a self-aligned manner during formation thereof, and a hydrogen barrier film formed on the insulating film.
    Type: Grant
    Filed: September 1, 2004
    Date of Patent: November 3, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Kumura, Yoshiro Shimojo, Iwao Kunishima, Tohru Ozaki
  • Patent number: 7573084
    Abstract: According to an aspect of the present invention, there is provided a non-volatile semiconductor memory device, including a ferroelectric capacitor being stacked a first electrode, a ferroelectric film and a second electrode in order, a first protective film with hydrogen barrier performance, the first protective film being formed under the first electrode and on a side-wall of the ferroelectric capacitor, the first protective film being widened from the second electrode towards the first electrode, a second protective film with hydrogen barrier performance, the second protective film being formed over the second electrode and on the first protective film formed on the side-wall of the ferroelectric capacitor, the second protective film being widened from the first electrode towards the second electrode, a cell transistor, a source of the cell transistor being connected to the first electrode, a drain of the cell transistor being connected to a bit line and a gate being connected to a word line.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: August 11, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshinori Kumura, Tohru Ozaki, Iwao Kunishima