Patents by Inventor Tatsuya Iwasaki

Tatsuya Iwasaki 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: 7872259
    Abstract: An object of the present invention is to provide a new light-emitting device with the use of an amorphous oxide. The light-emitting device has a light-emitting layer existing between first and second electrodes and a field effect transistor, of which the active layer is an amorphous.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: January 18, 2011
    Assignees: Canon Kabushiki Kaisha, Tokyo Institute of Technology
    Inventors: Tohru Den, Tatsuya Iwasaki, Hideo Hosono, Toshio Kamiya, Kenji Nomura
  • Publication number: 20110008584
    Abstract: The present invention aims at providing a novel oxide fluorescent material. The novel oxide fluorescent material is a fluorescent material including: as constituent elements, at least one or more elements selected from the group consisting of Mg, Ca, Sr and Ba; at least one or more elements selected from the group consisting of Si and Ge; at least one or more elements selected from the group consisting of rare earth elements; and oxygen, wherein the crystal structure is a pseudowollastonite crystal structure. The fluorescent substance includes a layer 54 comprised of the fluorescent material and a layer 52 including at least one or more elements selected from the group consisting of Si and Ge, the layers stacked on a substrate 51. The fluorescent substance includes an adjacent layer that includes at least one or more elements selected from the group consisting of Si and Ge and is in contact with the portion constituted by the fluorescent material.
    Type: Application
    Filed: September 21, 2010
    Publication date: January 13, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: TOMOYUKI OIKE, Yoshihiro Ohashi, Tatsuya Iwasaki
  • Patent number: 7847362
    Abstract: A photo detector includes a photoelectric conversion layer having a periodic structure made of a semiconductor material on a surface of the photoelectric conversion layer. In the photo detector, at least a part of a resonance region formed by the periodic structure is included in the photoelectric conversion layer of the photo detector.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: December 7, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaya Ogino, Tatsuya Iwasaki
  • Patent number: 7829444
    Abstract: Provided is a novel method for manufacturing a field effect transistor. Prior to forming an amorphous oxide layer on a substrate, ultraviolet rays are irradiated onto the substrate surface in an ozone atmosphere, plasma is irradiated onto the substrate surface, or the substrate surface is cleaned by a chemical solution containing hydrogen peroxide.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: November 9, 2010
    Assignees: Canon Kabushiki Kaisha, Tokyo Institute of Technology
    Inventors: Hisato Yabuta, Masafumi Sano, Tatsuya Iwasaki, Hideo Hosono, Toshio Kamiya, Kenji Nomura
  • Publication number: 20100276689
    Abstract: An amorphous oxide containing hydrogen (or deuterium) is applied to a channel layer of a transistor. Accordingly, a thin film transistor having superior TFT properties can be realized, the superior TFT properties including a small hysteresis, normally OFF operation, a high ON/OFF ratio, a high saturated current, and the like. Furthermore, as a method for manufacturing a channel layer made of an amorphous oxide, film formation is performed in an atmosphere containing a hydrogen gas and an oxygen gas, so that the carrier concentration of the amorphous oxide can be controlled.
    Type: Application
    Filed: July 9, 2010
    Publication date: November 4, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Tatsuya Iwasaki
  • Publication number: 20100279462
    Abstract: An amorphous oxide containing hydrogen (or deuterium) is applied to a channel layer of a transistor. Accordingly, a thin film transistor having superior TFT properties can be realized, the superior TFT properties including a small hysteresis, normally OFF operation, a high ON/OFF ratio, a high saturated current, and the like. Furthermore, as a method for manufacturing a channel layer made of an amorphous oxide, film formation is performed in an atmosphere containing a hydrogen gas and an oxygen gas, so that the carrier concentration of the amorphous oxide can be controlled.
    Type: Application
    Filed: July 9, 2010
    Publication date: November 4, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Tatsuya Iwasaki
  • Publication number: 20100276685
    Abstract: An amorphous oxide at least includes: at least one element selected from the group consisting of In, Zn, and Sn; and Mo. An atomic composition ratio of Mo to a number of all metallic atoms in the amorphous oxide is 0.1 atom % or higher and 5 atom % or lower.
    Type: Application
    Filed: December 25, 2008
    Publication date: November 4, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Naho Itagaki, Amita Goyal, Tatsuya Iwasaki
  • Publication number: 20100264419
    Abstract: A field-effect transistor includes at least a channel layer, a gate insulating layer, a source electrode, a drain electrode, and a gate electrode, which are formed on a substrate. The channel layer is made of an amorphous oxide material that contains at least In and B, and the amorphous oxide material has an element ratio B/(In+B) of 0.05 or higher and 0.29 or lower.
    Type: Application
    Filed: January 20, 2009
    Publication date: October 21, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Iwasaki, Amita Goyal, Naho Itagaki
  • Publication number: 20100267198
    Abstract: Provided is a novel method for manufacturing a field effect transistor. Prior to forming an amorphous oxide layer on a substrate, ultraviolet rays are irradiated onto the substrate surface in an ozone atmosphere, plasma is irradiated onto the substrate surface, or the substrate surface is cleaned by a chemical solution containing hydrogen peroxide.
    Type: Application
    Filed: June 28, 2010
    Publication date: October 21, 2010
    Applicants: CANON KABUSHIKI KAISHA, TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: HISATO YABUTA, MASAFUMI SANO, TATSUYA IWASAKI, HIDEO HOSONO, Toshio Kamiya, KENJI NOMURA
  • Publication number: 20100258794
    Abstract: A field effect transistor is provided including a gate electrode (15), a source electrode (13), a drain electrode (14) and a channel layer (11) to control current flowing between the source electrode (13) and the drain electrode (14) by applying a voltage to the gate electrode (15). The channel layer (11) is constituted of an amorphous oxide containing In and Si and having a compositional ratio expressed by Si/(In+Si) of not less than 0.05 and not more than 0.40.
    Type: Application
    Filed: August 29, 2008
    Publication date: October 14, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Iwasaki, Naho Itagaki
  • Patent number: 7807956
    Abstract: A current detection circuit detects photoelectric current that flows through a phototransistor, and outputs a current, which is proportional to the photoelectric current, via an output terminal. An input-side transistor is a PNP bipolar transistor, and is provided on a current path for the phototransistor. Output-side transistors are PNP bipolar transistors. The base terminals thereof are connected to that of the input-side transistor so as to form a common base terminal, and the emitter terminals thereof are connected to that of the input-side transistor so as to form a common emitter terminal, thereby forming a current mirror circuit. Each of first switches is provided between the collector of the corresponding output-side transistor and an output terminal. Each of second switches is provided between the collector of the corresponding output-side transistor and the ground terminal. A control unit controls the ON/OFF operations of the first switches and the second switches.
    Type: Grant
    Filed: October 20, 2008
    Date of Patent: October 5, 2010
    Assignee: Rohm Co., Ltd.
    Inventors: Tatsuya Iwasaki, Koki Tamakawa, Isao Yamamoto
  • Publication number: 20100224870
    Abstract: A field effect transistor includes at least a channel layer, a gate insulation layer, a source electrode, a drain electrode, and a gate electrode. The channel layer is formed from an amorphous oxide material that contains at least In and Mg, and an element ratio, expressed by Mg/(In+Mg), of the amorphous oxide material is 0.1 or higher and 0.48 or lower.
    Type: Application
    Filed: December 2, 2008
    Publication date: September 9, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Iwasaki, Naho Itagaki
  • Patent number: 7791082
    Abstract: It is an object of the present invention to provide a technology of controlling a threshold voltage of a thin film transistor in which an amorphous oxide film is applied to a channel layer. There is provided a semiconductor apparatus including a plurality of kinds of transistors, each of the plurality of kinds of transistors including a channel layer made of an amorphous oxide containing a plurality of kinds of metal elements; and threshold voltages of the plurality of kinds of transistors are different from one another by changing an element ratio of the amorphous oxide.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: September 7, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsuya Iwasaki
  • Patent number: 7791074
    Abstract: An amorphous oxide containing hydrogen (or deuterium) is applied to a channel layer of a transistor. Accordingly, a thin film transistor having superior TFT properties can be realized, the superior TFT properties including a small hysteresis, normally OFF operation, a high ON/OFF ratio, a high saturated current, and the like. Furthermore, as a method for manufacturing a channel layer made of an amorphous oxide, film formation is performed in an atmosphere containing a hydrogen gas and an oxygen gas, so that the carrier concentration of the amorphous oxide can be controlled.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: September 7, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsuya Iwasaki
  • Publication number: 20100221420
    Abstract: A phosphor film high in efficiency and less in luminescence irregularity and a method of producing the phosphor film are provided. The phosphor film includes a zinc sulfide compound containing an additive element(s). The additive element is at least one element selected from the group consisting of Ag, Cu and Au; the concentration of the additive element is 0.2 mol % or more and 5 mol % or less with respect to Zn; and the film thickness of the phosphor film is 10 nm or more and 2 um or less.
    Type: Application
    Filed: May 13, 2010
    Publication date: September 2, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomoyuki Oike, Tatsuya Iwasaki
  • Patent number: 7768031
    Abstract: To provide a DC drive type inorganic light emitting device excellent in luminous efficiency, provided is a light emitting device, including: a substrate; and a first layer and a second layer laminated on the substrate, in which the second layer is formed of a first portion containing Zn and at least one element chosen from S and Se as its constituent elements; and a second portion containing at least one element chosen from Cu and Ag and at least one element chosen from S and Se as its constituent elements; the first layer is made of a light emitting layer formed of at least one element chosen from S and Se and of Zn; and, in the second layer, the second portion has a cross section parallel to the substrate which tapers toward the first layer.
    Type: Grant
    Filed: February 21, 2007
    Date of Patent: August 3, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Naho Itagaki, Tomoyuki Oike, Tatsuya Iwasaki, Toru Den
  • Publication number: 20100148170
    Abstract: A field-effect transistor provided with at least a semiconductor layer and a gate electrode disposed over the above-described semiconductor layer with a gate insulating film therebetween, wherein the above-described semiconductor layer includes a first amorphous oxide semiconductor layer having at least one element selected from the group of Zn and In, and a second amorphous oxide semiconductor layer having at least one element selected from the group of Ge and Si and at least one element selected from the group of Zn and In. The composition of the above-described first amorphous oxide semiconductor layer is different from the composition of the above-described second amorphous oxide semiconductor layer.
    Type: Application
    Filed: December 9, 2009
    Publication date: June 17, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Miki Ueda, Tatsuya Iwasaki, Naho Itagaki, Amita Goyal
  • Patent number: 7737438
    Abstract: A method for manufacturing a field-effect transistor includes the steps of forming a source electrode and a drain electrode each containing hydrogen or deuterium; forming an oxide semiconductor layer in which the electrical resistance is decreased if hydrogen or deuterium is added; and, causing hydrogen or deuterium to diffuse from the source electrode and the drain electrode to the oxide semiconductor layer.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: June 15, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ayanori Endo, Ryo Hayashi, Tatsuya Iwasaki
  • Publication number: 20100140611
    Abstract: In a field effect transistor, a channel layer of the field effect transistor is composed of an amorphous oxide including In, Zn, N and O, an atomic composition ratio of N to N and O (N/(N+O)) in the amorphous oxide is equal to or larger than 0.01 atomic percent and equal to or smaller than 3 atomic percent, and the amorphous oxide does not include Ga, or, in a case where the amorphous oxide includes Ga, the number of Ga atoms contained in the amorphous oxide is smaller than the number of N atoms.
    Type: Application
    Filed: May 22, 2008
    Publication date: June 10, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Naho Itagaki, Tatsuya Iwasaki
  • Publication number: 20100109002
    Abstract: Provided is an oxynitride semiconductor comprising a metal oxynitride. The metal oxynitride contains Zn and at least one element selected from the group consisting of In, Ga, Sn, Mg, Si, Ge, Y, Ti, Mo, W, and Al. The metal oxynitride has an atomic composition ratio of N, N/(N+O), of 7 atomic percent or more to 80 atomic percent or less.
    Type: Application
    Filed: April 23, 2008
    Publication date: May 6, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Naho Itagaki, Tatsuya Iwasaki, Masatoshi Watanabe, Toru Den