Patents by Inventor Isamu Asano

Isamu Asano 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: 20220238658
    Abstract: Some embodiments include an integrated assembly having a gate material, an insulative material adjacent the gate material, and a semiconductor oxide adjacent the insulative material. The semiconductor oxide has a channel region proximate the gate material and spaced from the gate material by the insulative material. An electric field along the gate material induces carrier flow within the channel region, with the carrier flow being along a first direction. The semiconductor oxide includes a grain boundary having a portion which extends along a second direction that crosses the first direction of the carrier flow. In some embodiments, the semiconductor oxide has a grain boundary which extends along the first direction and which is offset from the insulative material by an intervening portion of the semiconductor oxide. The carrier flow is within the intervening region and substantially parallel to the grain boundary. Some embodiments include methods of forming integrated assemblies.
    Type: Application
    Filed: April 13, 2022
    Publication date: July 28, 2022
    Applicant: Micron Technology, Inc.
    Inventors: Yi Fang Lee, Isamu Asano, Ramanathan Gandhi, Scott E. Sills
  • Patent number: 11329133
    Abstract: Some embodiments include an integrated assembly having a gate material, an insulative material adjacent the gate material, and a semiconductor oxide adjacent the insulative material. The semiconductor oxide has a channel region proximate the gate material and spaced from the gate material by the insulative material. An electric field along the gate material induces carrier flow within the channel region, with the carrier flow being along a first direction. The semiconductor oxide includes a grain boundary having a portion which extends along a second direction that crosses the first direction of the carrier flow. In some embodiments, the semiconductor oxide has a grain boundary which extends along the first direction and which is offset from the insulative material by an intervening portion of the semiconductor oxide. The carrier flow is within the intervening region and substantially parallel to the grain boundary. Some embodiments include methods of forming integrated assemblies.
    Type: Grant
    Filed: November 19, 2019
    Date of Patent: May 10, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Yi Fang Lee, Isamu Asano, Ramanathan Gandhi, Scott E. Sills
  • Publication number: 20200161434
    Abstract: Some embodiments include an integrated assembly having a gate material, an insulative material adjacent the gate material, and a semiconductor oxide adjacent the insulative material. The semiconductor oxide has a channel region proximate the gate material and spaced from the gate material by the insulative material. An electric field along the gate material induces carrier flow within the channel region, with the carrier flow being along a first direction. The semiconductor oxide includes a grain boundary having a portion which extends along a second direction that crosses the first direction of the carrier flow. In some embodiments, the semiconductor oxide has a grain boundary which extends along the first direction and which is offset from the insulative material by an intervening portion of the semiconductor oxide. The carrier flow is within the intervening region and substantially parallel to the grain boundary. Some embodiments include methods of forming integrated assemblies.
    Type: Application
    Filed: November 19, 2019
    Publication date: May 21, 2020
    Applicant: Micron Technology, Inc.
    Inventors: Yi Fang Lee, Isamu Asano, Ramanathan Gandhi, Scott E. Sills
  • Publication number: 20140367630
    Abstract: A semiconductor device includes: a lower electrode, a heater electrode having a pillar shape erected on the lower electrode, a phase change material in contact with the upper portion of the heater electrode, an upper electrode disposed above a heater electrode via the phase change material, side wall portions enclosing the periphery of the heater electrode, a first insulating film configuring a bottom surface portion continuous between heater electrodes, and a second insulating film formed on a bottom surface portion of the first insulating film; wherein the first insulating film and the second insulating film are formed after the heater electrode is formed in a pillar shape by double patterning.
    Type: Application
    Filed: June 16, 2014
    Publication date: December 18, 2014
    Inventor: ISAMU ASANO
  • Patent number: 8637843
    Abstract: Disclosed herein is a device that includes: an interlayer insulation film having a through hole; and a phase change storage element provided in the through hole. The phase change storage element includes: an outer electrode being a conductive film of cylindrical shape and being formed along an inner wall of the through hole; a buffer insulation film being an insulation film of cylindrical shape and being formed along an inner wall of the outer electrode, an upper end of the buffer insulation film being recessed in part to form a recess; a phase change film filling an interior of the recess; and an inner electrode being a conductive film formed along an inner wall of the buffer insulation film including a surface of the phase change film.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: January 28, 2014
    Inventor: Isamu Asano
  • 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
  • Patent number: 8335106
    Abstract: To include a superlattice laminate having laminated thereon a first crystal layer of which crystal lattice is a cubic crystal and in which positions of constituent atoms are reversibly replaced by application of energy, and a second crystal layer having a composition different from that of the first crystal layer, and an orientation layer that is an underlaying layer of the superlattice laminate and causes a laminated surface of the first crystal layer to be (111)-orientated. According to the present invention, the laminated surface of the first crystal layer can be (111)-orientated by using the orientation layer as an underlaying layer. In the first crystal layer of which laminated surface is (111)-orientated, a crystal structure reversibly changes when a relatively low energy is applied. Therefore, characteristics of a superlattice device having this crystal layer can be enhanced.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: December 18, 2012
    Assignee: Elpida Memory, Inc.
    Inventors: Kazuo Aizawa, Isamu Asano, Junji Tominaga, Alexander Kolobov, Paul Fons, Robert Simpson
  • Patent number: 8295080
    Abstract: A solid-state memory device includes: a superlattice laminate having plural crystal layers laminated therein, the crystal layers including first and second crystal layers having mutually opposite compositions; a lower electrode provided on a first surface in a laminating direction of the superlattice laminate; and an upper electrode provided on a second surface of the superlattice laminate in the laminating direction. The first crystal layer included in the superlattice laminate is made of a phase change compound. According to the present invention, the superlattice laminate laminated in opposite directions of the upper and lower electrodes is sandwiched between these electrodes. Therefore, when an electric energy is applied to the superlattice laminate via these electrodes, a uniform electric energy can be applied to a laminated surface of the superlattice laminate. Accordingly, fluctuation of a resistance is small even when information is repeatedly rewritten, and data can be read stably as a result.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: October 23, 2012
    Assignee: Elpida Memory, Inc.
    Inventors: Kazuo Aizawa, Isamu Asano, Junji Tominaga, Alexander Kolobov, Paul Fons, Robert Simpson
  • Publication number: 20120211715
    Abstract: Disclosed herein is a device that includes: an interlayer insulation film having a through hole; and a phase change storage element provided in the through hole. The phase change storage element includes: an outer electrode being a conductive film of cylindrical shape and being formed along an inner wall of the through hole; a buffer insulation film being an insulation film of cylindrical shape and being formed along an inner wall of the outer electrode, an upper end of the buffer insulation film being recessed in part to form a recess; a phase change film filling an interior of the recess; and an inner electrode being a conductive film formed along an inner wall of the buffer insulation film including a surface of the phase change film.
    Type: Application
    Filed: February 10, 2012
    Publication date: August 23, 2012
    Inventor: Isamu ASANO
  • 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
  • Patent number: 8129709
    Abstract: A nonvolatile memory device (21) is provided with a semiconductor substrate, a plurality of active regions (3) formed on the semiconductor substrate and extending in a band, a plurality of select active elements (23) formed in the active regions (3) and having a first impurity diffusion region and a second impurity diffusion region, a plurality of first electrodes (13) electrically connected to the first impurity diffusion region, a variable resistance layer (12) electrically connected to the first electrodes (13), and a plurality of second electrodes electrically connected to the variable resistance layer (12). Among the plurality of first electrodes (13) and the plurality of second electrodes, an array direction of at least one pair of the first electrodes (13) and the second electrodes that are electrically connected to the same variable resistance layer (12), and a direction of extension of the activation regions (3) are not parallel.
    Type: Grant
    Filed: November 13, 2009
    Date of Patent: March 6, 2012
    Assignee: Elpida Memory, Inc.
    Inventors: Akiyoshi Seko, Yukio Fuji, Natsuki Sato, Isamu Asano
  • Patent number: 7985693
    Abstract: An area where a lower electrode is in contact with a variable resistance material needs to be reduced to lower the power consumption of a variable resistance memory device. The present invention is to provide a method of producing a variable resistance memory element whereby the lower electrode can be formed smaller. Combining an anisotropic etching process with an isotropic etching process enables the lower electrode to be formed smaller.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: July 26, 2011
    Assignee: Elpida Memory, Inc.
    Inventors: Akiyoshi Seko, Natsuki Sato, Isamu Asano
  • Patent number: 7959755
    Abstract: This invention relates to a method of manufacturing a thermal laminate by laminating a first substrate film layer and a second substrate film layer through an adhesive resin layer, which involves the steps of, integrating the adhesive resin layer with the first substrate film layer, heating the surface of the adhesive resin layer by heat rays in the presence of oxygen to induce functional groups which contribute to adhesion, and then, superimposing the second substrate film layer on the adhesive resin layer to be bonded thereto with pressure. The thermal laminate has a strong laminated strength without using a solvent, and is excellent in the safety and hygiene of foods.
    Type: Grant
    Filed: April 26, 2004
    Date of Patent: June 14, 2011
    Assignees: Nakamoto Packs Co., Ltd., Nissei Chemical Co., Ltd.
    Inventors: Toshiyuki Narumiya, Isamu Asano, Hiroshi Kasahara, Ryoji Tanaka
  • Publication number: 20100315867
    Abstract: A solid-state memory device includes: a superlattice laminate having plural crystal layers laminated therein, the crystal layers including first and second crystal layers having mutually opposite compositions; a lower electrode provided on a first surface in a laminating direction of the superlattice laminate; and an upper electrode provided on a second surface of the superlattice laminate in the laminating direction. The first crystal layer included in the superlattice laminate is made of a phase change compound. According to the present invention, the superlattice laminate laminated in opposite directions of the upper and lower electrodes is sandwiched between these electrodes. Therefore, when an electric energy is applied to the superlattice laminate via these electrodes, a uniform electric energy can be applied to a laminated surface of the superlattice laminate. Accordingly, fluctuation of a resistance is small even when information is repeatedly rewritten, and data can be read stably as a result.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 16, 2010
    Applicant: ELPIDA MEMORY, INC
    Inventors: Kazuo AIZAWA, Isamu ASANO, Junji TOMINAGA, Alexander KOLOBOV, Paul FONS, Robert SIMPSON
  • 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
  • Publication number: 20100284218
    Abstract: To include a superlattice laminate having laminated thereon a first crystal layer of which crystal lattice is a cubic crystal and in which positions of constituent atoms are reversibly replaced by application of energy, and a second crystal layer having a composition different from that of the first crystal layer, and an orientation layer that is an underlaying layer of the superlattice laminate and causes a laminated surface of the first crystal layer to be (111)-orientated. According to the present invention, the laminated surface of the first crystal layer can be (111)-orientated by using the orientation layer as an underlaying layer. In the first crystal layer of which laminated surface is (111)-orientated, a crystal structure reversibly changes when a relatively low energy is applied. Therefore, characteristics of a superlattice device having this crystal layer can be enhanced.
    Type: Application
    Filed: May 3, 2010
    Publication date: November 11, 2010
    Applicant: Elpida Memory, Inc.
    Inventors: Kazuo AIZAWA, Isamu Asano, Junji Tominaga, Alexander Kolobov, Paul Fons, Robert Simpson
  • Patent number: 7723715
    Abstract: A radial memory device includes a phase-change material, a first electrode in electrical communication with the phase-change material, the first electrode having a first area of electrical communication with the phase-change material. A second electrode in electrical communication with the phase-change material, the second electrode having a second area of electrical communication with the phase-change material, and the second area being laterally spacedly disposed from the first area. Additionally, the radial memory device includes a dielectric layer disposed between the first electrode and the second electrode, the dielectric layer having an opening therethrough, the phase-change material being disposed in the opening, wherein the phase-change material is disposed at least partially above the second electrode. Further, a method of making a memory device is disclosed.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: May 25, 2010
    Assignee: Ovonyx, Inc.
    Inventors: Wolodymyr Czubatyj, Tyler Lowrey, Isamu Asano
  • Publication number: 20100123114
    Abstract: A nonvolatile memory device (21) is provided with a semiconductor substrate, a plurality of active regions (3) formed on the semiconductor substrate and extending in a band, a plurality of select active elements (23) formed in the active regions (3) and having a first impurity diffusion region and a second impurity diffusion region, a plurality of first electrodes (13) electrically connected to the first impurity diffusion region, a variable resistance layer (12) electrically connected to the first electrodes (13), and a plurality of second electrodes electrically connected to the variable resistance layer (12). Among the plurality of first electrodes (13) and the plurality of second electrodes, an array direction of at least one pair of the first electrodes (13) and the second electrodes that are electrically connected to the same variable resistance layer (12), and a direction of extension of the activation regions (3) are not parallel.
    Type: Application
    Filed: November 13, 2009
    Publication date: May 20, 2010
    Inventors: Akiyoshi SEKO, Yukio FUJI, Natsuki SATO, Isamu ASANO
  • Patent number: 7692272
    Abstract: A non-volatile memory element comprises a bottom electrode 12; a top electrode 15; and a recording layer 13 containing phase change material and a block layer 14 that can block phase change of the recording layer 13, provided between the bottom electrode 12 and the top electrode 15. The block layer 14 is constituted of material having an electrical resistance that is higher than that of material constituting the recording layer 13. The block layer 14 suppresses the radiation of heat towards the top electrode 15 and greatly limits the phase change region when a write current is applied. The result is a high heating efficiency. The top electrode 15 itself can be used to constitute a bit line, or a separate bit line can be provided.
    Type: Grant
    Filed: January 19, 2006
    Date of Patent: April 6, 2010
    Assignee: Elpida Memory, Inc.
    Inventors: Isamu Asano, Natsuki Sato, Wolodymyr Czubatyj, Jeffrey P. Fournier