Patents by Inventor Yoshiaki Ikuta

Yoshiaki Ikuta 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: 10928721
    Abstract: To provide a reflective mask blank for EUV lithography which is excellent in flatness, whereby the deterioration of the overlay accuracy at the time of pattern transfer can be relatively easily corrected, and the deterioration of the overlay accuracy due to the flatness is small.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: February 23, 2021
    Assignee: AGC, Inc.
    Inventor: Yoshiaki Ikuta
  • Patent number: 9739722
    Abstract: A process for inspecting an EUV mask blank capable of distinguishing phase defects and amplitude defects and capable of detecting small amplitude defects, a process for producing an EUV mask blank using the inspection process, and an EUV mask blank obtainable by such a process. A process for inspecting a reflective mask blank for EUV lithography having a multilayer reflective film and an absorber layer. The process includes a first step of detecting in-plane defects in the multilayer reflective film by applying EUV light to the surface of the multilayer reflective film, a second step of detecting in-plane defects from the absorber layer by applying light having a wavelength of from 150 to 600 nm to the surface of the absorber layer, and a step of distinguishing phase defects and amplitude defects in the reflective mask blank by comparison between the first and second in-plane defect data.
    Type: Grant
    Filed: October 8, 2015
    Date of Patent: August 22, 2017
    Assignee: Asahi Glass Company, Limited
    Inventors: Hiroshi Nakanishi, Junichi Kageyama, Yoshiaki Ikuta
  • Publication number: 20160357100
    Abstract: To provide a reflective mask blank for EUV lithography which is excellent in flatness, whereby the deterioration of the overlay accuracy at the time of pattern transfer can be relatively easily corrected, and the deterioration of the overlay accuracy due to the flatness is small.
    Type: Application
    Filed: May 31, 2016
    Publication date: December 8, 2016
    Applicant: Asahi Glass Company, Limited
    Inventor: Yoshiaki IKUTA
  • Publication number: 20160266482
    Abstract: A glass substrate for a mask blank includes two main surfaces facing each other, side surfaces and surfaces to be chamfered. The surfaces to be chamfered are provided peripherally around each of the two main surfaces. At least one of the side surfaces and the surfaces to be chamfered in the glass substrate has, in a measurement area with an atomic force microscope (AFM) of 3 ?m square, an arithmetic mean roughness (Ra) of 0.5 nm or less and a dale void volume (Vvv) obtained from a bearing area curve as defined in ISO 25178-2(2012) of 1.5×107 nm3 or less.
    Type: Application
    Filed: February 24, 2016
    Publication date: September 15, 2016
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Naohiro UMEO, Yoshiaki IKUTA, Yuzo OKAMURA
  • Publication number: 20160168020
    Abstract: The present invention relates to a method of finishing a pre-polished TiO2—SiO2 glass substrate, containing a step of measuring a striae-originated MSFR (MSFR0) of a major surface, a step of measuring a TiO2 concentration distribution (?TiO2) in the major surface, a first and second processing steps of processing the major surface, and a cleaning step of cleaning the major surface, in which according to the MSFR0 (nm) and the ?TiO2 (wt %), the total etching amount (nm) of a chemical etching amount of the major surface in the second processing step and another chemical etching amount of the major surface in the cleaning step is controlled to satisfy the following expression (1) Total etching amount?(10 nm?MSFR0)v/A/?TiO2 ??(1) (v is an average etching rate (nm/sec) and A is an TiO2 concentration dependency (nm/sec/wt %) of an etching rate).
    Type: Application
    Filed: December 1, 2015
    Publication date: June 16, 2016
    Applicant: Asahi Glass Company, Limited
    Inventors: Yuzo OKAMURA, Yusuke HIRABAYASHI, Yoshiaki IKUTA
  • Publication number: 20160109384
    Abstract: To provide a process for inspecting an EUV mask blank capable of distinguishing phase defects and amplitude defects and capable of detecting even amplitude defects of small sizes, a process for producing an EUV mask blank using the inspection process, and an EUV mask blank obtainable by such a process.
    Type: Application
    Filed: October 8, 2015
    Publication date: April 21, 2016
    Applicant: Asahi Glass Company, Limited
    Inventors: Hiroshi NAKANISHI, Junichi Kageyama, Yoshiaki Ikuta
  • Patent number: 9268207
    Abstract: A method of manufacturing a reflective mask blank for EUV lithography with a resist film, includes preparing a reflective mask blank provided with three or more concave or convex fiducial marks each formed by at least two lines placed to extend along any one of virtual lines that cross at an intersection point, at least one of the lines of the fiducial mark being placed to extend along each of the virtual lines; forming a resist film on the reflective mask blank; detecting fiducial positions corresponding to the intersection points of the fiducial marks by scanning with an electron beam or an ultraviolet light; and exposing specific areas of the resist film including circular areas centered at the fiducial positions of the respective fiducial marks with a radius of 1.5W, where W is the maximum value of a width of the line of the respective fiducial marks.
    Type: Grant
    Filed: March 26, 2015
    Date of Patent: February 23, 2016
    Assignee: Asahi Glass Company, Limited
    Inventor: Yoshiaki Ikuta
  • Publication number: 20160041463
    Abstract: The present invention relates to a glass substrate for optical lithography containing a fluorine-containing synthetic quartz glass, in which the glass substrate has a pattern forming region, and when the pattern forming region is divided into a plural parts each having a strip shape along a long side direction of the pattern forming region such that the number of divisions is greater than or equal to 3, each part has an average fluorine concentration of greater than or equal to 1 mass % and a distribution of the average fluorine concentration among the parts is less than or equal to 0.45 mass %.
    Type: Application
    Filed: August 5, 2015
    Publication date: February 11, 2016
    Applicant: Asahi Glass Company, Limited
    Inventors: Yoshiaki Ikuta, Masaaki Takata
  • Patent number: 9120842
    Abstract: It is an objective of the present invention to identify SPARC protein-derived peptides that are able to induce human killer T cells and helper T cells having cytotoxic activity to tumors, and to provide a means for carrying out a tumor immunotherapy of patients with various types of cancers overexpressing SPARC. The present invention provides a peptide of any of the following: (A) a peptide which consists of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3; or (B) a peptide which consists of an amino acid sequence comprising a substitution or addition of one or several amino acids with respect to the peptide consisting of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3, and which has capacity to induce cytotoxic (killer) T cells.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: September 1, 2015
    Assignee: ONCO THERAPY SCIENCE, INC.
    Inventors: Yasuharu Nishimura, Yoshiaki Ikuta, Shuichi Nakatsuru
  • Publication number: 20150198874
    Abstract: A method of manufacturing a reflective mask blank for EUV lithography with a resist film, includes preparing a reflective mask blank provided with three or more concave or convex fiducial marks each formed by at least two lines placed to extend along any one of virtual lines that cross at an intersection point, at least one of the lines of the fiducial mark being placed to extend along each of the virtual lines; forming a resist film on the reflective mask blank; detecting fiducial positions corresponding to the intersection points of the fiducial marks by scanning with an electron beam or an ultraviolet light; and exposing specific areas of the resist film including circular areas centered at the fiducial positions of the respective fiducial marks with a radius of 1.5W, where W is the maximum value of a width of the line of the respective fiducial marks.
    Type: Application
    Filed: March 26, 2015
    Publication date: July 16, 2015
    Applicant: Asahi Glass Company, Limited
    Inventor: Yoshiaki IKUTA
  • Patent number: 8993201
    Abstract: Provided are an EUV mask blank in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, a reflective layer-equipped substrate to be used for producing the EUV mask blank, and a process for producing the reflective layer-equipped substrate. A reflective layer-equipped substrate for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: March 31, 2015
    Assignee: Asahi Glass Company, Limited
    Inventors: Masaki Mikami, Mitsuhiko Komakine, Yoshiaki Ikuta
  • Patent number: 8921017
    Abstract: The present invention relates to a multilayer substrate containing a substrate and a multilayer film provided on the substrate, in which a concave or convex fiducial mark that indicates a fiducial position of the multilayer substrate is formed on the surface of the multilayer film on the opposite side to the side of the substrate; and a material of at least a part of the surface of the fiducial mark is different from a material of a most superficial layer of the multilayer film on the opposite side to the side of the substrate.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: December 30, 2014
    Assignee: Asahi Glass Company, Limited
    Inventors: Yuzo Okamura, Yoshiaki Ikuta
  • Patent number: 8916316
    Abstract: The present invention relates to a reflective mask blank containing in this order, a substrate, a multilayer reflective film that reflects exposure light, and an absorber layer that absorbs the exposure light, in which the reflective mask blank further contains a fiducial mark indicating a reference position of the multilayer reflective film, which is formed in a concave shape or in a convex shape on a surface of the multilayer reflective film or on a surface of one layer formed between the multilayer reflective film and the absorber layer, and the fiducial mark is formed so as to have a reflectivity different from an area surrounding the fiducial mark with respect to a light with a prescribed wavelength and is transferred to a layer formed on the fiducial mark.
    Type: Grant
    Filed: March 4, 2014
    Date of Patent: December 23, 2014
    Assignee: Asahi Glass Company, Limited
    Inventors: Yuzo Okamura, Yoshiaki Ikuta
  • Publication number: 20140186753
    Abstract: The present invention relates to a reflective mask blank containing in this order, a substrate, a multilayer reflective film that reflects exposure light, and an absorber layer that absorbs the exposure light, in which the reflective mask blank further contains a fiducial mark indicating a reference position of the multilayer reflective film, which is formed in a concave shape or in a convex shape on a surface of the multilayer reflective film or on a surface of one layer formed between the multilayer reflective film and the absorber layer, and the fiducial mark is formed so as to have a reflectivity different from an area surrounding the fiducial mark with respect to a light with a prescribed wavelength and is transferred to a layer formed on the fiducial mark.
    Type: Application
    Filed: March 4, 2014
    Publication date: July 3, 2014
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Yuzo OKAMURA, Yoshiaki IKUTA
  • Publication number: 20140011123
    Abstract: The present invention relates to a multilayer substrate containing a substrate and a multilayer film provided on the substrate, in which a concave or convex fiducial mark that indicates a fiducial position of the multilayer substrate is formed on the surface of the multilayer film on the opposite side to the side of the substrate; and a material of at least a part of the surface of the fiducial mark is different from a material of a most superficial layer of the multilayer film on the opposite side to the side of the substrate.
    Type: Application
    Filed: September 9, 2013
    Publication date: January 9, 2014
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Yuzo OKAMURA, Yoshiaki IKUTA
  • Patent number: 8580465
    Abstract: Provided are a multilayer mirror for EUVL in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, and a process for its production. A multilayer mirror for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: November 12, 2013
    Assignee: Asahi Glass Company, Limited
    Inventors: Masaki Mikami, Mitsuhiko Komakine, Yoshiaki Ikuta
  • Publication number: 20130288363
    Abstract: It is an objective of the present invention to identify SPARC protein-derived peptides that are able to induce human killer T cells and helper T cells having cytotoxic activity to tumors, and to provide a means for carrying out a tumor immunotherapy of patients with various types of cancers overexpressing SPARC. The present invention provides a peptide of any of the following: (A) a peptide which consists of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3; or (B) a peptide which consists of an amino acid sequence comprising a substitution or addition of one or several amino acids with respect to the peptide consisting of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3, and which has capacity to induce cytotoxic (killer) T cells.
    Type: Application
    Filed: May 23, 2013
    Publication date: October 31, 2013
    Inventors: Yasuharu NISHIMURA, Yoshiaki IKUTA, Shuichi NAKATSURU
  • Patent number: 8518613
    Abstract: The present invention relates to a method for producing an optical member base material for EUVL, comprising performing the following in this order to obtain an optical member base material for EUVL: a preliminary-polishing step of preliminarily polishing a film forming surface and a back surface of the film forming surface of a glass substrate; a measuring step of measuring a total thickness distribution and a flatness of the glass substrate; and a corrective-polishing step of locally polishing only the back surface of the glass substrate depending on the measurement result of the measuring step.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: August 27, 2013
    Assignee: Asahi Glass Company, Limited
    Inventors: Hiroshi Nakanishi, Yoshiaki Ikuta
  • Patent number: 8470968
    Abstract: It is an objective of the present invention to identify SPARC protein-derived peptides that are able to induce human killer T cells and helper T cells having cytotoxic activity to tumors, and to provide a means for carrying out a tumor immunotherapy of patients with various types of cancers overexpressing SPARC. The present invention provides a peptide of any of the following: (A) a peptide which consists of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3; or (B) a peptide which consists of an amino acid sequence comprising a substitution or addition of one or several amino acids with respect to the peptide consisting of the amino acid sequence as shown in any one of SEQ ID NOS: 1 to 3, and which has capacity to induce cytotoxic (killer) T cells.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: June 25, 2013
    Assignee: Onco Therapy Science, Inc.
    Inventors: Yasuharu Nishimura, Yoshiaki Ikuta, Shuichi Nakatsuru
  • Patent number: 8402786
    Abstract: A process for producing a synthetic silica glass optical component which contains at least 1×1017 molecules/cm3 and has an OH concentration of at most 200 ppm and substantially no reduction type defects, by treating a synthetic silica glass having a hydrogen molecule content of less than 1×1017 molecules/cm3 at a temperature of from 300 to 600° C. in a hydrogen gas-containing atmosphere at a pressure of from 2 to 30 atms.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: March 26, 2013
    Assignee: Asahi Glass Company, Limited
    Inventors: Yoshiaki Ikuta, Shinya Kikugawa, Akio Masui, Noriaki Shimodaira, Shuhei Yoshizawa