Patents by Inventor Tatsuo ASAKAWA

Tatsuo ASAKAWA 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: 20200192213
    Abstract: A substrate with an electrically conductive film for fabricating a reflective mask is obtained that is capable of preventing positional shift of the reflective mask during pattern transfer. Provided is a substrate with an electrically conductive film used in lithography, the substrate with an electrically conductive film having an electrically conductive film formed on one of the main surfaces of a mask blank substrate, and a coefficient of static friction of the surface of the electrically conductive film is not less than 0.25.
    Type: Application
    Filed: February 20, 2020
    Publication date: June 18, 2020
    Applicant: HOYA CORPORATION
    Inventors: Takumi KOBAYASHI, Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Tsutomu SHOKI
  • Patent number: 10606166
    Abstract: A substrate with an electrically conductive film for fabricating a reflective mask is obtained that is capable of preventing positional shift of the reflective mask during pattern transfer. Provided is a substrate with an electrically conductive film used in lithography, the substrate with an electrically conductive film having an electrically conductive film formed on one of the main surfaces of a mask blank substrate, and a coefficient of static friction of the surface of the electrically conductive film is not less than 0.25.
    Type: Grant
    Filed: June 8, 2016
    Date of Patent: March 31, 2020
    Assignee: HOYA CORPORATION
    Inventors: Takumi Kobayashi, Kazuhiro Hamamoto, Tatsuo Asakawa, Tsutomu Shoki
  • Patent number: 10347485
    Abstract: The present invention aims to provide a reflective mask blank and a reflective mask which have a highly smooth multilayer reflective film as well as a low number of defects, and methods of manufacturing the same, and aims to prevent charge-up during a mask defect inspection using electron beams.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: July 9, 2019
    Assignee: HOYA CORPORATION
    Inventors: Tsutomu Shoki, Tatsuo Asakawa, Hirofumi Kozakai
  • Patent number: 10191365
    Abstract: A reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein the root mean square roughness (Rms), obtained by measuring a 3 ?m×3 ?m region on the surface of the reflective mask blank on which the mask blank multilayer film is formed with an atomic force microscope, is not more than 0.5 nm and the power spectrum density at a spatial frequency of 1 ?m?1 to 10 ?m?1 is not more than 50 nm4.
    Type: Grant
    Filed: June 27, 2017
    Date of Patent: January 29, 2019
    Assignee: HOYA CORPORATION
    Inventors: Kazuhiro Hamamoto, Tatsuo Asakawa, Tsutomu Shoki
  • Publication number: 20180149962
    Abstract: A substrate with an electrically conductive film for fabricating a reflective mask is obtained that is capable of preventing positional shift of the reflective mask during pattern transfer. Provided is a substrate with an electrically conductive film used in lithography, the substrate with an electrically conductive film having an electrically conductive film formed on one of the main surfaces of a mask blank substrate, and a coefficient of static friction of the surface of the electrically conductive film is not less than 0.25.
    Type: Application
    Filed: June 8, 2016
    Publication date: May 31, 2018
    Applicant: HOYA CORPORATION
    Inventors: Takumi KOBAYASHI, Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Tsutomu SHOKI
  • Publication number: 20170329215
    Abstract: A reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein the root mean square roughness (Rms), obtained by measuring a 3 ?m×3 ?m region on the surface of the reflective mask blank on which the mask blank multilayer film is formed with an atomic force microscope, is not more than 0.5 nm and the power spectrum density at a spatial frequency of 1 ?m?1 to 10 ?m?1 is not more than 50 nm4.
    Type: Application
    Filed: June 27, 2017
    Publication date: November 16, 2017
    Applicant: HOYA CORPORATION
    Inventors: KAZUHIRO HAMAMOTO, TATSUO ASAKAWA, TSUTOMU SHOKI
  • Publication number: 20170263444
    Abstract: The present invention aims to provide a reflective mask blank and a reflective mask which have a highly smooth multilayer reflective film as well as a low number of defects, and methods of manufacturing the same, and aims to prevent charge-up during a mask defect inspection using electron beams.
    Type: Application
    Filed: September 14, 2015
    Publication date: September 14, 2017
    Applicant: HOYA CORPORATION
    Inventors: Tsutomu SHOKI, Tatsuo ASAKAWA, Hirofumi KOZAKAI
  • Patent number: 9726969
    Abstract: A reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein, in the relationship between bearing area (%) and bearing depth (nm) as measured with an atomic force microscope for a 1 ?m×1 ?m region of the surface of the reflective mask blank on which the mask blank multilayer film is formed, the surface of the reflective mask blank satisfies the relationship of (BA70?BA30)/(BD70?BD30)?60(%/nm) and maximum height (Rmax)?4.5 nm.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: August 8, 2017
    Assignee: HOYA CORPORATION
    Inventors: Kazuhiro Hamamoto, Tatsuo Asakawa, Tsutomu Shoki
  • Patent number: 9720315
    Abstract: Provided is a reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein the root mean square roughness (Rms), obtained by measuring a 3 ?m×3 ?m region on the surface of the reflective mask blank on which the mask blank multilayer film is formed with an atomic force microscope, is not more than 0.5 nm and the power spectrum density at a spatial frequency of 1 ?m?1 to 10 ?m?1 is not more than 50 nm4.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: August 1, 2017
    Assignee: Hoya Corporation
    Inventors: Kazuhiro Hamamoto, Tatsuo Asakawa, Tsutomu Shoki
  • Patent number: 9535318
    Abstract: This invention provides a reflective mask blank capable of preventing peeling-off of a multilayer reflective film due to cleaning or the like in a mask manufacturing process or during mask use. The reflective mask blank includes a multilayer reflective film, a protective film, an absorber film, and a resist film formed in this order on a substrate. Assuming that a distance from the center of the substrate to an outer peripheral end of the multilayer reflective film is L(ML), that a distance from the center of the substrate to an outer peripheral end of the protective film is L(Cap), that a distance from the center of the substrate to an outer peripheral end of the absorber film is L(Abs), and that a distance from the center of the substrate to an outer peripheral end of the resist film is L(Res), L(Abs)>L(Res)>L(Cap)?L(ML) and the outer peripheral end of the resist film is located inward of an outer peripheral end of the substrate.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: January 3, 2017
    Assignee: HOYA CORPORATION
    Inventors: Kazuhiro Hamamoto, Tatsuo Asakawa, Osamu Maruyama, Tsutomu Shoki
  • Publication number: 20160282711
    Abstract: This invention provides a reflective mask blank capable of preventing peeling-off of a multilayer reflective film due to cleaning or the like in a mask manufacturing process or during mask use. The reflective mask blank includes a multilayer reflective film, a protective film, an absorber film, and a resist film formed in this order on a substrate. Assuming that a distance from the center of the substrate to an outer peripheral end of the multilayer reflective film is L(ML), that a distance from the center of the substrate to an outer peripheral end of the protective film is L(Cap), that a distance from the center of the substrate to an outer peripheral end of the absorber film is L(Abs), and that a distance from the center of the substrate to an outer peripheral end of the resist film is L(Res), L(Abs)>L(Res)>L(Cap)?L(ML) and the outer peripheral end of the resist film is located inward of an outer peripheral end of the substrate.
    Type: Application
    Filed: June 10, 2016
    Publication date: September 29, 2016
    Applicant: HOYA CORPORATION
    Inventors: Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Osamu MARUYAMA, Tsutomu SHOKI
  • Publication number: 20160238925
    Abstract: A reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein, in the relationship between bearing area (%) and bearing depth (nm) as measured with an atomic force microscope for a 1 ?m×1 ?m region of the surface of the reflective mask blank on which the mask blank multilayer film is formed, the surface of the reflective mask blank satisfies the relationship of (BA70?BA30)/(BD70?BD30)?60(%/nm) and maximum height (Rmax)?4.5 nm.
    Type: Application
    Filed: August 29, 2014
    Publication date: August 18, 2016
    Applicant: HOYA CORPORATION
    Inventors: Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Tsutomu SHOKI
  • Patent number: 9377679
    Abstract: This invention provides a reflective mask blank capable of preventing peeling-off of a multilayer reflective film due to cleaning or the like in a mask manufacturing process or during mask use. The reflective mask blank includes a multilayer reflective film, a protective film, an absorber film, and a resist film formed in this order on a substrate. Assuming that a distance from the center of the substrate to an outer peripheral end of the multilayer reflective film is L(ML), that a distance from the center of the substrate to an outer peripheral end of the protective film is L(Cap), that a distance from the center of the substrate to an outer peripheral end of the absorber film is L(Abs), and that a distance from the center of the substrate to an outer peripheral end of the resist film is L(Res), L(Abs)>L(Res)>L(Cap)?L(ML) and the outer peripheral end of the resist film is located inward of an outer peripheral end of the substrate.
    Type: Grant
    Filed: July 27, 2013
    Date of Patent: June 28, 2016
    Assignee: HOYA CORPORATION
    Inventors: Kazuhiro Hamamoto, Tatsuo Asakawa, Osamu Maruyama, Tsutomu Shoki
  • Publication number: 20160161837
    Abstract: Provided is a reflective mask blank capable of facilitating the discovery of contaminants, scratches and other critical defects by inhibiting the detection of pseudo defects attributable to surface roughness of a substrate or film in a defect inspection using a highly sensitive defect inspection apparatus. The reflective mask blank has a mask blank multilayer film comprising a multilayer reflective film, obtained by alternately laminating a high refractive index layer and a low refractive index layer, and an absorber film on a main surface of a mask blank substrate, wherein the root mean square roughness (Rms), obtained by measuring a 3 ?m×3 ?m region on the surface of the reflective mask blank on which the mask blank multilayer film is formed with an atomic force microscope, is not more than 0.5 nm and the power spectrum density at a spatial frequency of 1 ?m?1 to 10 ?m?1 is not more than 50 nm4.
    Type: Application
    Filed: August 29, 2014
    Publication date: June 9, 2016
    Applicant: HOYA CORPORATION
    Inventors: Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Tsutomu SHOKI
  • Publication number: 20150301441
    Abstract: This invention provides a reflective mask blank capable of preventing peeling-off of a multilayer reflective film due to cleaning or the like in a mask manufacturing process or during mask use. The reflective mask blank includes a multilayer reflective film, a protective film, an absorber film, and a resist film formed in this order on a substrate. Assuming that a distance from the center of the substrate to an outer peripheral end of the multilayer reflective film is L(ML), that a distance from the center of the substrate to an outer peripheral end of the protective film is L(Cap), that a distance from the center of the substrate to an outer peripheral end of the absorber film is L(Abs), and that a distance from the center of the substrate to an outer peripheral end of the resist film is L(Res), L(Abs)>L(Res)>L(Cap)?L(ML) and the outer peripheral end of the resist film is located inward of an outer peripheral end of the substrate.
    Type: Application
    Filed: July 27, 2013
    Publication date: October 22, 2015
    Applicant: HOYA CORPORATION
    Inventors: Kazuhiro HAMAMOTO, Tatsuo ASAKAWA, Osamu MARUYAMA, Tsutomu SHOKI