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: 7961586
    Abstract: An information recording/reproducing device according to an example of the present invention includes first and second heads, a recording medium having a data area from which recording data is read by the first head and a servo burst area from which a servo burst signal is read by the second head, a driver which performs positioning of the second head based on the servo burst signal, and a resistor which covers a surface of the servo burst area and does not cover a surface of the data area. The recording data and the servo burst signal are recorded by a pulse signal.
    Type: Grant
    Filed: August 24, 2007
    Date of Patent: June 14, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kohichi Kubo, Takahiro Hirai, Shinya Aoki, Akihiro Koga, Junichi Akiyama, Shinji Takakura, Hiroaki Nakamura
  • Publication number: 20110073927
    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: Application
    Filed: September 20, 2010
    Publication date: March 31, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Takeshi ARAKI, Takeshi Yamaguchi, Mariko Hayashi, Kohichi Kubo, Takayuki Tsukamoto
  • Publication number: 20110062407
    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 first region is higher than that in the second region.
    Type: Application
    Filed: September 17, 2010
    Publication date: March 17, 2011
    Inventors: Chikayoshi KAMATA, Takayuki Tsukamoto, Takeshi Yamaguchi, Tsukasa Nakai, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Publication number: 20110062405
    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: Application
    Filed: September 24, 2010
    Publication date: March 17, 2011
    Inventors: Takayuki Tsukamoto, Chikayoshi Kamata, Takeshi Yamaguchi, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Publication number: 20110057246
    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: Application
    Filed: September 20, 2010
    Publication date: March 10, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Takeshi ARAKI, Takeshi YAMAGUCHI, Mariko HAYASHI, Kohichi KUBO, Takayuki TSUKAMOTO
  • Publication number: 20110037046
    Abstract: According to one embodiment, a resistance-change memory includes a laminated structure in which a lower electrode, an insulating film and an upper electrode are stacked, and a resistance-change film provided on a side surface of the laminated structure, and configured to store data in accordance with an electric resistance change.
    Type: Application
    Filed: July 12, 2010
    Publication date: February 17, 2011
    Inventors: Mitsuru SATO, Kohichi Kubo, Chikayoshi Kamata, Noriko Bota
  • Publication number: 20110031463
    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: Application
    Filed: July 27, 2010
    Publication date: February 10, 2011
    Inventors: Mitsuru SATO, Kohichi Kubo, Chikayoshi Kamata, Noriko Bota
  • Publication number: 20110031459
    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: Application
    Filed: September 20, 2010
    Publication date: February 10, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kohichi KUBO, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Tsukasa Nakai, Toshiro Hiraoka
  • Publication number: 20110026294
    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: Application
    Filed: September 20, 2010
    Publication date: February 3, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Takayuki Tsukamoto, Takeshi Yamaguchi, Chikayoshi Kamata, Tsukasa Nakai, Takahiro Hirai, Shinya Aoki, Kohichi Kubo
  • Publication number: 20110024713
    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: Application
    Filed: August 18, 2010
    Publication date: February 3, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Chikayoshi KAMATA, Takayuki Tsukamoto, Kohichi Kubo, Shinya Aoki, Takahiro Hirai, Toshiro Hiraoka
  • Publication number: 20110006277
    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: Application
    Filed: September 20, 2010
    Publication date: January 13, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kohichi KUBO, Chikayoshi KAMATA, Takayuki TSUKAMOTO, Shinya AOKI, Takahiro HIRAI, Tsukasa NAKAI, Toshiro HIRAOKA
  • Publication number: 20100316831
    Abstract: According to one embodiment, an information recording and reproducing device includes a resistive layer directly or indirectly added to a recording layer and having electric resistivity larger than electric resistivity in the low-resistance state of the recording layer. A first compound contained in the recording layer comprises a composite compound includes two or more kinds of cationic elements, at least one of the two or more kinds of cationic elements is a transition element having a d orbit filled incompletely with electrons, a shortest distance between cationic elements adjacent to each other is 0.32 nm or less.
    Type: Application
    Filed: August 20, 2010
    Publication date: December 16, 2010
    Inventors: Kohichi Kubo, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Toshiro Hiraoka
  • Patent number: 7852739
    Abstract: A probe memory device carries out positioning with the use of a servo pattern provided in a servo area on a recording medium, and the recording medium and a probe head section are reciprocatingly moved (scan-moved) by vibration at a specific frequency in a one-axis direction. At this time, based on information from the servo area, relative position information between the recording medium and the probe head section is acquired, the relative position information is processed at a control section, and then, feedback control is carried out for carrying out position correction relative to an actuator.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: December 14, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Koga, Shinji Takakura, Hiroaki Nakamura, Kohichi Kubo, Takahiro Hirai, Junichi Akiyama
  • Patent number: 7838877
    Abstract: There is proposed a nonvolatile information recording and reproducing device with low power consumption and high thermal stability. The information recording and reproducing apparatus according to an aspect of the present invention includes a recording layer and a unit for recording information by applying a voltage to the recording layer to generate a state change in the recording layer. The recording layer being configured to include at least a first compound having a hollandite structure.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: November 23, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinya Aoki, Kohichi Kubo, Takayuki Tsukamoto, Chikayoshi Kamata, Takahiro Hirai, Toshiro Hiraoka
  • Publication number: 20100238703
    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: Application
    Filed: September 21, 2009
    Publication date: September 23, 2010
    Inventors: Kohichi KUBO, Hirofumi Inoue, Mitsuru Sato, Chikayoshi Kamata, Shinya Aoki, Noriko Bota
  • Publication number: 20100142091
    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: Application
    Filed: December 11, 2009
    Publication date: June 10, 2010
    Inventors: Takayuki TSUKAMOTO, Kohichi Kubo, Chikayoshi Kamata, Takahiro Hirai, Shinya Aoki, Toshiro Hiraoka
  • Publication number: 20100142262
    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: Application
    Filed: December 11, 2009
    Publication date: June 10, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takayuki TSUKAMOTO, Kohichi KUBO, Chikayoshi KAMATA, Takahiro HIRAI, Shinya AOKI, Toshiro HIRAOKA
  • Publication number: 20100142261
    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: Application
    Filed: December 11, 2009
    Publication date: June 10, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kohichi KUBO, Chikayoshi Kamata, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Toshiro Hiraoka
  • Publication number: 20100127235
    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: Application
    Filed: December 11, 2009
    Publication date: May 27, 2010
    Inventors: Takayuki TSUKAMOTO, Kohichi Kubo, Chikayoshi Kamata, Takahiro Hirai, Shinya Aoki, Toshiro Hiraoka
  • Publication number: 20100074001
    Abstract: The information recording/reproducing device includes a stacked structure which is comprised of an electrode layer and a recording layer, a buffer layer which contacts with the 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 is comprised of a complex compound having two cations, and one of the cations is a transition element having ā€œdā€ orbit where electrons are incompletely filled. The recording layer is comprised of CuxAyXz (0.1?x?1.1, 0.9?y?1.1, 1.8?z?2.2), and includes a first chemical compound having a delafossite structure. The buffer layer is comprised of one of M3N4, M3N5, MN2, M4O7, MO2 and M2O5.
    Type: Application
    Filed: September 21, 2009
    Publication date: March 25, 2010
    Inventors: Kohichi Kubo, Takayuki Tsukamoto, Shinya Aoki, Takahiro Hirai, Chikayoshi Kamata, Toshiro Hiraoka