Patents by Inventor Kohichi Kubo

Kohichi Kubo 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).

  • Patent number: 8698228
    Abstract: According to one embodiment, a non-volatile memory device includes a stacked structure and a voltage application portion. The stacked structure includes a memory portion, and an electrode stacked with the memory portion and having a surface having a portion facing the memory portion. The voltage application portion applies a voltage to the memory portion to cause a change in a resistance in the memory portion to store information. The surface includes a first region and a second region. The first region contains at least one of a metallic element, Si, Ga, and As. The first region is conductive. The second region contains at least one of the metallic element, Si, Ga, and As, and has a content ratio of nonmetallic element higher than a content ratio of nonmetallic element in the first region. At least one of the first region and the second region has an anisotropic shape on the surface.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: April 15, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takeshi Araki, Takeshi Yamaguchi, Mariko Hayashi, Kohichi Kubo, Takayuki Tsukamoto
  • Patent number: 8581424
    Abstract: According to one embodiment, an information recording/reproducing device including a semiconductor substrate, a first interconnect layer on the semiconductor substrate, a first memory cell array layer on the first interconnect layer, and a second interconnect layer on the first memory cell array layer. The first memory cell array layer comprises an insulating layer having an alignment mark, and a stacked layer structure on the insulating layer and including a storage layer and an electrode layer. All of the layers in the stacked layer structure comprises a material with a permeability of visible light of 1% or more.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: November 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Hirai, Tsukasa Nakai, Kohichi Kubo, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki
  • Patent number: 8475903
    Abstract: According to one embodiment, an information recording/reproducing device includes a recording layer, and a recording circuit configured to record information by generating a phase change in the recording layer while applying a voltage to the recording layer. The recording layer comprises a compound including at least one type of cationic element, and at least one type of anionic element, at least the one type of cationic element is a transition element including a d orbital incompletely filled with electrons, and the average shortest distance between adjacent cationic elements is 0.32 nm or less, and the recording layer is provided with a material selected from (i) AxMyX4 (0?x?2.2, 1.8?y?3), (ii) AxMyX3 (0?x?1.1, 0.9?y?3), and (iii) AxMyX4 (0?x?1.1, 0.9?y?3).
    Type: Grant
    Filed: December 27, 2011
    Date of Patent: July 2, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kohichi Kubo
  • Patent number: 8431920
    Abstract: According to one embodiment, an information recording and reproducing device includes a recording layer which includes a typical element and a transition element, and stores a state of a first electric resistivity and a state of a second electric resistivity different from the first electric resistivity by a movement of the typical element, and an electrode layer which is disposed at one end of the recording layer to apply a voltage or a current to the recording layer. The recording layer includes a first region which is in contact with the electrode layer and the electrode layer includes a second region which is in contact with the recording layer. The first and second regions are opposite to each other. And the first and second regions include the typical element, and a concentration of the typical element in the second region is higher than that in the first region.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: April 30, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Chikayoshi Kamata, Takayuki Tsukamoto, Takeshi Yamaguchi, Tsukasa Nakai, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Patent number: 8421051
    Abstract: According to one embodiment, a resistance-change memory includes a variable resistance element having a laminated structure in which a first electrode, a resistance-change film and a second electrode are laminated, and set to a low-resistance state and a high-resistance state according to stored data, an insulating film provided on a side surface of the variable resistance element, and a fixed resistance element provided on a side surface of the insulating film, and includes a conductive film, the fixed resistance element being connected in parallel with the variable resistance element.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: April 16, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mitsuru Sato, Kohichi Kubo, Chikayoshi Kamata, Noriko Bota
  • Patent number: 8410540
    Abstract: According to one embodiment, a non-volatile memory device includes a stacked structure including a memory portion and an electrode having a surface facing the memory portion; and a voltage application portion to apply a voltage to the memory portion to change resistance. The surface includes first and second regions. The first region contains a first nonmetallic element and at least one element of a metallic element, Si, Ga, and As. The second region contains a second nonmetallic element and the at least one element. The second region has a content ratio of the second nonmetallic element higher than that in the first region. A difference in electronegativity between the second nonmetallic element and the at least one element is greater than that between the first nonmetallic element and the at least one element. At least one of the first and second regions has an anisotropic shape.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: April 2, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takeshi Araki, Takeshi Yamaguchi, Mariko Hayashi, Kohichi Kubo, Takayuki Tsukamoto
  • Patent number: 8391045
    Abstract: An information recording/reproducing device includes a first electrode layer, a second electrode layer, a recording layer as a variable resistance between the first and second electrode layer, and a circuit which supplies a voltage to the recording layer to change a resistance of the recording layer. Each of the first and second electrode layers is comprised of IV or III-V semiconductor doped with p-type carrier or n-type carrier.
    Type: Grant
    Filed: September 21, 2009
    Date of Patent: March 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Kubo, Hirofumi Inoue, Mitsuru Sato, Chikayoshi Kamata, Shinya Aoki, Noriko Bota
  • Patent number: 8305797
    Abstract: According to one embodiment, an information recording/reproducing device includes a recording layer and a driver section. The recording layer has a first layer including a first compound. The first compound includes a mixed crystal of a first oxide containing a first metallic element and a second oxide. The second oxide has a crystal structure being same as the first oxide and contains a second metallic element different from the first metallic element. The driver section is configured to produce state change in the recording layer to record information by at least one of application of voltage to the recording layer and passage of current to the recording layer. Composition ratio of an element having a smaller ionic radius of the first and second metallic elements is not less than percolation threshold of a lattice formed of ions of the first and second metallic elements based on the crystal structure.
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: November 6, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinya Aoki, Kohichi Kubo, Takayuki Tsukamoto, Takahiro Hirai, Chikayoshi Kamata, Tsukasa Nakai
  • Patent number: 8288748
    Abstract: According to one embodiment, an information recording and reproducing device includes a first layer, a second layer, and a recording layer between the first and second layers, which is capable of a transition between a first state of a low resistance and a second state of a high resistance by flowing a current between the first and second layers. A peripheral portion of the recording layer has a composition different from that of a center portion of the recording layer. The center portion includes two kinds of cation elements. And the center portion is different from the peripheral portion in a ratio of the two kinds of cation elements.
    Type: Grant
    Filed: September 24, 2010
    Date of Patent: October 16, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Chikayoshi Kamata, Takeshi Yamaguchi, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Patent number: 8269205
    Abstract: According to one embodiment, an information recording and reproducing device includes a first layer, a second layer and a recording layer. The recording layer is provided between the first layer and the second layer and being capable of reversibly changing between a first state having a first resistance and a second state having a second resistance higher than the first resistance. The recording layer includes a first compound layer and a second compound layer. The first compound layer contains a first compound. The first compound includes a first cation element and a second cation element of a type different from the first cation element. The second compound layer contains a second compound. The second compound includes a transition element having a d-orbital partially filled with electron, and the second compound includes a void site capable of storing at least one of the first cation element and the second cation element.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: September 18, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Kubo, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Tsukasa Nakai, Toshiro Hiraoka
  • Patent number: 8237145
    Abstract: According to one embodiment, a nonvolatile memory device includes a stacked body including a first layer, a second layer and a recording layer. The recording layer is provided between the first layer and the second layer. The recording layer is capable of reversibly changing between a first state and a second state having a resistance higher than a resistance in the first state by a current supplied via the first layer and the second layer. The recording layer includes a first portion and a second portion provided in a plane of a major surface of the recording layer. The second portion has a nitrogen amount higher than a nitrogen amount in the first portion.
    Type: Grant
    Filed: August 18, 2010
    Date of Patent: August 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Chikayoshi Kamata, Takayuki Tsukamoto, Kohichi Kubo, Shinya Aoki, Takahiro Hirai, Toshiro Hiraoka
  • Publication number: 20120163090
    Abstract: According to one embodiment, an information recording/reproducing device includes a recording layer, and a recording circuit configured to record information by generating a phase change in the recording layer while applying a voltage to the recording layer. The recording layer comprises a compound including at least one type of cationic element, and at least one type of anionic element, at least the one type of cationic element is a transition element including a d orbital incompletely filled with electrons, and the average shortest distance between adjacent cationic elements is 0.32 nm or less, and the recording layer is provided with a material selected from (i) AxMyX4 (0?x?2.2, 1.8?y?3), (ii) AxMyX3 (0?x?1.1, 0.9?y?3), and (iii) AxMyX4 (0?x?1.1, 0.9?y?3).
    Type: Application
    Filed: December 27, 2011
    Publication date: June 28, 2012
    Inventor: Kohichi KUBO
  • Patent number: 8207518
    Abstract: According to one embodiment, an information recording and reproducing device includes a first layer, a second layer and a recording layer. The recording layer is provided between the first layer and the second layer and being capable of reversibly changing between a first state having a first resistance and a second state having a second resistance higher than the first resistance by a current supplied via the first layer and the second layer. The recording layer includes a first compound layer and an insulating layer. The first compound layer contains a first compound. The first compound includes a first cation element and a second cation element of a type different from the first cation element. The insulating layer contains a third compound, and the third compound includes an element selected from group 1 to 4 elements and group 12 to 17 elements in the periodic table.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: June 26, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Kubo, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Tsukasa Nakai, Toshiro Hiraoka
  • Patent number: 8188455
    Abstract: An information recording/reproducing device includes a recording layer, and a recording circuit which records data to the recording layer by generating a phase change in the recording layer. The recording layer includes a first chemical compound having a spinel structure. The recording layer is AxMyX4 (0.1?x?2.2, 1.0?y?2.0), where A includes one selected from a group of Zn, Cd and Hg, M includes one selected from a group of Ti, Zr, Hf, V, Nb and Ta, and X includes O.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: May 29, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Kohichi Kubo, Chikayoshi Kamata, Takahiro Hirai, Shinya Aoki, Toshiro Hiraoka
  • Publication number: 20120061732
    Abstract: According to one embodiment, an information recording/reproducing device including a semiconductor substrate, a first interconnect layer on the semiconductor substrate, a first memory cell array layer on the first interconnect layer, and a second interconnect layer on the first memory cell array layer. The first memory cell array layer comprises an insulating layer having an alignment mark, and a stacked layer structure on the insulating layer and including a storage layer and an electrode layer. All of the layers in the stacked layer structure comprises a material with a permeability of visible light of 1% or more.
    Type: Application
    Filed: September 9, 2011
    Publication date: March 15, 2012
    Inventors: Takahiro HIRAI, Tsukasa NAKAI, Kohichi KUBO, Chikayoshi KAMATA, Takayuki TSUKAMOTO, Shinya AOKI
  • Patent number: 8089796
    Abstract: According to one embodiment, an information recording and reproducing device includes a first layer, a second layer and a recording layer. The recording layer is provided between the first and second layers and is capable of reversibly transitioning between a first state and a second state with a resistance higher than in the first state. One of the first and second layers includes a resistivity distribution layer perpendicular to a stacking direction of the first and second layers, and the recording layer. The resistivity distribution layer includes a low and a high resistivity portion. Resistivity of the high resistivity portion is higher than resistivity of the low resistivity portion. The low resistivity portion contains a transition element identical to a transition element contained in the high resistivity portion.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: January 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Takeshi Yamaguchi, Chikayoshi Kamata, Tsukasa Nakai, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Patent number: 8018762
    Abstract: An information recording and reproducing apparatus, includes: a stacked structure including an electrode layer and a recording layer; a buffer layer added to the electrode layer; and a voltage application unit configured to apply a voltage to the recording layer, produce a phase change in the recording layer, and record information. The recording layer includes a first layer including a first compound having an ilmenite structure represented by AxMyX3 (0.1?x?1.1 and 0.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: September 13, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Kubo, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Toshiro Hiraoka
  • Publication number: 20110216576
    Abstract: According to one embodiment, an information recording/reproducing device includes a recording layer and a driver section. The recording layer has a first layer including a first compound. The first compound includes a mixed crystal of a first oxide containing a first metallic element and a second oxide. The second oxide has a crystal structure being same as the first oxide and contains a second metallic element different from the first metallic element. The driver section is configured to produce state change in the recording layer to record information by at least one of application of voltage to the recording layer and passage of current to the recording layer. Composition ratio of an element having a smaller ionic radius of the first and second metallic elements is not less than percolation threshold of a lattice formed of ions of the first and second metallic elements based on the crystal structure.
    Type: Application
    Filed: March 9, 2011
    Publication date: September 8, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shinya Aoki, Kohichi Kubo, Takayuki Tsukamoto, Takahiro Hirai, Chikayoshi Kamata, Tsukasa Nakai
  • Patent number: 8014189
    Abstract: An information recording/reproducing device includes a recording layer, and a recording circuit which records data to the recording layer by generating a phase change in the recording layer. The recording layer includes a first chemical compound having a spinel structure. The recording layer is AxMyX4 (0.1?x?2.2, 1.0?y?2.0), where A includes one selected from a group of Zn, Cd and Hg, M includes one selected from a group of Cr, Mo, W, Mn and Re, and X includes O.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: September 6, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Kohichi Kubo, Chikayoshi Kamata, Takahiro Hirai, Shinya Aoki, Toshiro Hiraoka
  • Patent number: 7995382
    Abstract: An information recording and reproducing apparatus, includes: a recording layer including a first layer including a first compound, the first compound being a conjugated compound including at least two types of cation elements, at least one selected from the cation elements being a transition element having a d orbit incompletely filled by electrons, a shortest distance between adjacent cation elements being not more than 0.32 nm; a voltage application unit that applies a voltage to the recording layer, produces a phase change in the recording layer, and records information; an electrode layer that applies a voltage to the recording layer; and an orientation control layer provided between the recording layer and the electrode layer to control an orientation of the recording layer.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: August 9, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Kohichi Kubo, Chikayoshi Kamata, Takahiro Hirai, Shinya Aoki, Toshiro Hiraoka