Patents by Inventor Kazushi Hayashi

Kazushi Hayashi 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: 20220274952
    Abstract: An object of the present invention is to provide a cyclic azine compound exhibiting both excellent driving voltage characteristics and excellent current efficiency characteristics. The desired cyclic azine compound has a specific structure represented by formula (1).
    Type: Application
    Filed: July 22, 2020
    Publication date: September 1, 2022
    Applicants: TOSOH CORPORATION, SAGAMI CHEMICAL RESEARCH INSTITUTE
    Inventors: Naoki UCHIDA, Hidenori AIHARA, Takuya YAMAGATA, Naoki HAYAKAWA, Natsumi NAKAJIMA, Kazuki HATTORI, Fuminari UEHARA, Yohei ONO, Masaya HIRANO, Yuta MORINAKA, Keisuke NOMURA, Eriko OHTA, Tomohiro SHONO, Kana OIKE, Kazushi HAYASHI, Keiya AOYAGI, Kosuke SATO, Toshiki NISHIURA
  • Patent number: 10475711
    Abstract: A quality evaluation method for an oxide semiconductor thin film includes: selecting a peak value having a largest calculated value and a time constant for the peak value among calculated values obtained by substituting each signal value for respective elapsed times after stopping excitation light irradiation and the corresponding elapsed time into the following Equation (1); and estimating, from the peak value and the time constant, an energy level of defect state and the defect density in the oxide semiconductor thin film: x=(signal value)×(elapsed time for the signal value)??Equation 1.
    Type: Grant
    Filed: April 26, 2017
    Date of Patent: November 12, 2019
    Assignee: Kobe Steel, Ltd.
    Inventors: Kazushi Hayashi, Mototaka Ochi, Toshihiro Kugimiya
  • Publication number: 20190122941
    Abstract: A quality evaluation method for an oxide semiconductor thin film includes: selecting a peak value having a largest calculated value and a time constant for the peak value among calculated values obtained by substituting each signal value for respective elapsed times after stopping excitation light irradiation and the corresponding elapsed time into the following Equation (1); and estimating, from the peak value and the time constant, an energy level of defect state and the defect density in the oxide semiconductor thin film: x=(signal value)×(elapsed time for the signal value)??Equation 1.
    Type: Application
    Filed: April 26, 2017
    Publication date: April 25, 2019
    Applicant: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.)
    Inventors: Kazushi HAYASHI, Mototaka OCHI, Toshihiro KUGIMIYA
  • Patent number: 10203367
    Abstract: Provided is a method for simply evaluating defects caused in interface states in oxide semiconductor thin films and protective films in TFTs having protective films formed on the surface of oxide semiconductor thin films without actually measuring the characteristics of the same. This evaluation method evaluates defects caused in the interface states by measuring electron states in the oxide semiconductor thin film by a contact method or noncontact method. The defects caused in the interface states are any of the following: (1) threshold value voltage (Vth) when a positive bias is applied to the thin-film transistor, (2) difference in threshold value voltage (?Vth) before and after applying the positive bias to the thin-film transistor, and (3) threshold value during the first measurement when a plurality of measurements is made of the threshold value voltage when a positive bias is applied to the thin-film transistor.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: February 12, 2019
    Assignee: Kobe Steel, Ltd.
    Inventors: Kazushi Hayashi, Aya Miki, Nobuyuki Kawakami
  • Patent number: 10090208
    Abstract: Provided are: a method for measuring and evaluating (predicting or estimating) stress stability of an oxide semiconductor thin film in a contactless manner; and a quality control method for an oxide semiconductor. This evaluation method comprises a first step and a second step. The first step includes: subjecting an oxide semiconductor thin film to irradiation with both excitation light and microwave radiation; stopping the irradiation with the excitation light after the maximum intensity of reflected wave of the microwave radiation, which varies with the irradiation of the excitation light, from the thin film has been observed; and thereafter measuring a variation in the reflectance with which the microwave radiation is reflected by the thin film. The second step includes: calculating, from the variation in the reflectance, a parameter that corresponds to slow attenuation observed about 1 ?s after the stopping; and thus evaluating the stress stability of the oxide semiconductor.
    Type: Grant
    Filed: January 9, 2014
    Date of Patent: October 2, 2018
    Assignee: Kobe Steel, Ltd.
    Inventors: Tomoya Kishi, Kazushi Hayashi, Toshihiro Kugimiya
  • Publication number: 20180219220
    Abstract: A negative electrode for use in an iron-air secondary battery of the present invention comprises a three-dimensionally formed structure in which particles of metal powder comprising iron or an iron alloy as a principal component are coupled to each other through metallic bonding, wherein the negative electrode has a porosity of greater than or equal to 30% and less than or equal to 70%. A production method of a negative electrode for an iron-air secondary battery of the present invention comprises: mixing with a resin, metal powder comprising iron or an iron alloy as a principle component; molding a mixture obtained after the mixing; and sintering a molded body obtained after the molding.
    Type: Application
    Filed: June 2, 2016
    Publication date: August 2, 2018
    Applicants: KABUSHIKI KAISHA KOBE SEIKO SHO (Kobe Steel, Ltd.), NATIONAL UNIVERSITY CORPORATION TOYOHASHI UNIVERSITY OF TECHNOLOGY
    Inventors: Kazushi HAYASHI, Hisatoshi SAKAMOTO, Atsunori MATSUDA, Yasutaka MAEDA, Tsubasa SUZUKI
  • Patent number: 9816944
    Abstract: The present invention provides a method for accurately and easily measuring/evaluating/predicting/estimating the electrical resistance of an oxide semiconductor thin film, and a method for managing the film quality. The method for evaluating an oxide semiconductor thin film includes: a first step for irradiating, with excitation light and microwave, a sample on which an oxide semiconductor thin film is formed, measuring the maximum value of the reflected microwave by the thin film which changes due to the excitation light irradiation, then stopping the excitation light irradiation and measuring the change in reflectivity of the microwave from the thin film after the excitation light irradiation has been stopped; and a second step for calculating a parameter corresponding to the slow decay observed after the excitation light irradiation has been stopped from the change in the reflectivity and evaluating the electrical resistivity of the oxide semiconductor thin film.
    Type: Grant
    Filed: December 1, 2014
    Date of Patent: November 14, 2017
    Assignee: Kobe Steel, Ltd.
    Inventors: Kazushi Hayashi, Aya Miki, Toshihiro Kugimiya, Nobuyuki Kawakami
  • Patent number: 9780005
    Abstract: Provided is a method for reliably and simply evaluating the quality of an oxide semiconductor thin film and a laminated body having a protective film on the surface of this oxide semiconductor thin film. Also provided is a method for reliably and simply managing the quality of an oxide semiconductor thin film.
    Type: Grant
    Filed: July 6, 2015
    Date of Patent: October 3, 2017
    Assignee: Kobe Steel, Ltd.
    Inventors: Nobuyuki Kawakami, Kazushi Hayashi, Toshihiro Kugimiya, Mototaka Ochi
  • Publication number: 20170184660
    Abstract: Provided is a method for simply evaluating defects caused in interface states in oxide semiconductor thin films and protective films in TFTs having protective films formed on the surface of oxide semiconductor thin films without actually measuring the characteristics of the same. This evaluation method evaluates defects caused in the interface states by measuring electron states in the oxide semiconductor thin film by a contact method or noncontact method. The defects caused in the interface states are any of the following (1)-(3). (1) Threshold value voltage (Vth,) when a positive bias is applied to the thin-film transistor (2) Difference in threshold value voltage (?Vth) before and after applying the positive bias to the thin-film transistor (3) Threshold value during the first measurement when a plurality of measurements is made of the threshold value voltage when a positive bias is applied to the thin-film transistor.
    Type: Application
    Filed: June 22, 2015
    Publication date: June 29, 2017
    Applicant: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.)
    Inventors: Kazushi HAYASHI, Aya MIKI, Nobuyuki KAWAKAMI
  • Patent number: 9583633
    Abstract: In an oxide for a semiconductor layer of a thin film transistor according to the present invention, wherein metal elements constituting the oxide are In, Zn, and Sn, an oxygen partial pressure is 15% by volume or more when depositing the oxide in the semiconductor layer of the thin film transistor, and a defect density of the oxide satisfies 7.5×1015cm?3 or less, and a mobility satisfies 15 cm2/Vs or more.
    Type: Grant
    Filed: February 27, 2014
    Date of Patent: February 28, 2017
    Assignee: SAMSUNG DISPLAY CO., LTD.
    Inventors: Byung Du Ahn, Gun Hee Kim, Yeon-Hong Kim, Jin Hyun Park, Shuji Kosaka, Kazushi Hayashi
  • Publication number: 20160282284
    Abstract: The present invention provides a method for accurately and easily measuring/evaluating/predicting/estimating the electrical resistance of an oxide semiconductor thin film, and a method for managing the film quality. The method for evaluating an oxide semiconductor thin film includes: a first step for irradiating, with excitation light and microwave, a sample on which an oxide semiconductor thin film is formed, measuring the maximum value of the reflected microwave by the thin film which changes due to the excitation light irradiation, then stopping the excitation light irradiation and measuring the change in reflectivity of the microwave from the thin film after the excitation light irradiation has been stopped; and a second step for calculating a parameter corresponding to the slow decay observed after the excitation light irradiation has been stopped from the change in the reflectivity and evaluating the electrical resistivity of the oxide semiconductor thin film.
    Type: Application
    Filed: December 1, 2014
    Publication date: September 29, 2016
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Kazushi HAYASHI, Aya MIKI, Toshihiro KUGIMIYA, Nobuyuki KAWAKAMI
  • Publication number: 20160223462
    Abstract: An evaluation device for an oxide semiconductor thin film includes a first excitation light irradiation unit configured to irradiate a measurement region of a sample with first excitation light and to generate an electron-hole pair, an electromagnetic wave irradiation unit configured to irradiate with electromagnetic wave, a reflecting electromagnetic wave intensity detection unit configured to detect intensity of a reflected electromagnetic wave, a second excitation light irradiation unit configured to irradiate the sample with second excitation light and to generate photoluminescence light, an emission intensity measurement unit configured to measure emission intensity of the photoluminescence light, and an evaluation unit configured to evaluate mobility and stress stability. The first excitation light irradiation unit and the second excitation light irradiation unit are the same or different excitation light radiation units.
    Type: Application
    Filed: September 10, 2014
    Publication date: August 4, 2016
    Applicant: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.)
    Inventors: Kazushi HAYASHI, Tomoya KISHI
  • Publication number: 20160211384
    Abstract: In an oxide for a semiconductor layer of a thin film transistor according to the present invention, wherein metal elements constituting the oxide are In, Zn, and Sn, an oxygen partial pressure is 15% by volume or more when depositing the oxide in the semiconductor layer of the thin film transistor, and a defect density of the oxide satisfies 7.5×1015cm?3 or less, and a mobility satisfies 15 cm2/Vs or more.
    Type: Application
    Filed: February 27, 2014
    Publication date: July 21, 2016
    Inventors: BYUNG DU AHN, GUN HEE KIM, YEON-HONG KIM, JIN HYUN PARK, SHUJI KOSAKA, KAZUSHI HAYASHI
  • Patent number: 9316589
    Abstract: This method for evaluating an oxide semiconductor thin film includes evaluating the stress stability of an oxide semiconductor thin film on the basis of the light emission intensity of luminescent light excited when radiating an electron beam or excitation light at a sample at which the oxide semiconductor thin film is formed. The stress stability of the oxide semiconductor thin film is evaluated on the basis of the light emission intensity (L1) observed in the range of 1.6-1.9 eV of the luminescent light excited from the oxide semiconductor thin film.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: April 19, 2016
    Assignee: Kobe Steel, Ltd.
    Inventors: Kazushi Hayashi, Toshihiro Kugimiya, Tomoya Kishi, Aya Miki
  • Patent number: 9279762
    Abstract: In a semiconductor carrier lifetime measuring apparatus A1 of the present invention, at least two types of light having mutually different wavelengths are irradiated onto a semiconductor X to be measured, a predetermined measurement wave is irradiated onto the semiconductor X to be measured, a reflected wave of the measurement wave that has been reflected by the semiconductor X to be measured or a transmitted wave of the measurement wave that has transmitted through the semiconductor X to be measured is detected, and the carrier lifetime in the semiconductor X to be measured is obtained based on the detection results so as to minimize the error. Accordingly, the semiconductor carrier lifetime measuring apparatus A1 configured as described above can more accurately measure the carrier lifetime.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: March 8, 2016
    Assignees: Kobe Steel, Ltd., Kobelco Research Institute, Inc.
    Inventors: Kazushi Hayashi, Hiroyuki Takamatsu, Yoshito Fukumoto, Shingo Sumie
  • Publication number: 20150371906
    Abstract: Provided are: a method for measuring and evaluating (predicting or estimating) stress stability of an oxide semiconductor thin film in a contactless manner; and a quality control method for an oxide semiconductor. This evaluation method comprises a first step and a second step. The first step includes: subjecting an oxide semiconductor thin film to irradiation with both excitation light and microwave radiation; stopping the irradiation with the excitation light after the maximum intensity of reflected wave of the microwave radiation, which varies with the irradiation of the excitation light, from the thin film has been observed; and thereafter measuring a variation in the reflectance with which the microwave radiation is reflected by the thin film. The second step includes: calculating, from the variation in the reflectance, a parameter that corresponds to slow attenuation observed about 1 ?s after the stopping; and thus evaluating the stress stability of the oxide semiconductor.
    Type: Application
    Filed: January 9, 2014
    Publication date: December 24, 2015
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Tomoya KISHI, Kazushi HAYASHI, Toshihiro KUGIMIYA
  • Publication number: 20150364553
    Abstract: With respect to this oxide for a semiconductor layer of a thin film transistor, metal elements that constitute the oxide comprise In, Sn, Ga, and Zn, the oxygen partial pressure when forming the oxide film as the semiconductor layer of the thin film transistor is 15 volume % or lower (not including 0 volume %), the defect density of the oxide satisfies 2×1016 cm?3 or less, and the mobility satisfies 6.2 cm2/Vs or more.
    Type: Application
    Filed: February 27, 2014
    Publication date: December 17, 2015
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Shuji KOSAKA, Kazushi HAYASHI
  • Publication number: 20150355095
    Abstract: This method for evaluating an oxide semiconductor thin film includes evaluating the stress stability of an oxide semiconductor thin film on the basis of the light emission intensity of luminescent light excited when radiating an electron beam or excitation light at a sample at which the oxide semiconductor thin film is formed. The stress stability of the oxide semiconductor thin film is evaluated on the basis of the light emission intensity (L1) observed in the range of 1.6-1.9 eV of the luminescent light excited from the oxide semiconductor thin film.
    Type: Application
    Filed: September 4, 2013
    Publication date: December 10, 2015
    Inventors: Kazushi HAYASHI, Toshihiro KUGIMIYA, Tomoya KISHI, Aya MIKI
  • Publication number: 20150357474
    Abstract: With respect to this oxide for a semiconductor layer of a thin film transistor, metal elements that constitute the oxide comprise In, Ga, and Zn, the oxygen partial pressure when forming the oxide film as the semiconductor layer of the thin film transistor is 15 volume % or lower (not including 0 volume %), the defect density of the oxide satisfies 2×1016 cm?3 or less, and the mobility satisfies 6 cm2/Vs or more.
    Type: Application
    Filed: February 27, 2014
    Publication date: December 10, 2015
    Inventors: Shuji KOSAKA, Kazushi HAYASHI
  • Publication number: 20120203473
    Abstract: In a semiconductor carrier lifetime measuring apparatus A1 of the present invention, at least two types of light having mutually different wavelengths are irradiated onto a semiconductor X to be measured, a predetermined measurement wave is irradiated onto the semiconductor X to be measured, a reflected wave of the measurement wave that has been reflected by the semiconductor X to be measured or a transmitted wave of the measurement wave that has transmitted through the semiconductor X to be measured is detected, and the carrier lifetime in the semiconductor X to be measured is obtained based on the detection results so as to minimize the error. Accordingly, the semiconductor carrier lifetime measuring apparatus A1 configured as described above can more accurately measure the carrier lifetime.
    Type: Application
    Filed: October 1, 2010
    Publication date: August 9, 2012
    Applicants: KOBELCO RESEARCH INSTITUTE, INC., KABUSHIKI KAISHA KOBE SEIKO SHO
    Inventors: Kazushi Hayashi, Hiroyuki Takamatsu, Yoshito Fukumoto, Naokazu Sakoda, Masahiro Inui, Shingo Sumie