Patents by Inventor Masao Ushida

Masao Ushida 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: 7901842
    Abstract: It is provided a photomask blank that has good flatness when a light-shielding film is patterned and hence can provide a good mask pattern accuracy and a good pattern transfer accuracy, and a method of producing a photomask. A photomask blank of the present invention includes a light-shielding film containing at least chromium on a light-transmitting substrate. The light-shielding film is formed so as to cause a desired film stress in the direction opposite to that of a change in the film stress that is anticipated to be caused in the light-shielding film by heat treatment according to a resist film formed on the light-shielding film. A photomask is produced by patterning the light-shielding film of the photomask blank by dry etching.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: March 8, 2011
    Assignee: Hoya Corporation
    Inventors: Takeyuki Yamada, Yasushi Okubo, Masao Ushida, Hiroyuki Iwashita
  • Patent number: 7781125
    Abstract: A lithography mask blank used as a material for producing a lithography mask includes at least one thin film which is formed on a substrate and has a desired function. The blank has a nitrogen-containing thin film as the above-mentioned thin film and an ammonium ion production preventing layer for preventing production of ammonium ions, which is formed on the nitrogen-containing thin film or at least at a surface portion of the nitrogen-containing thin film and which is exposed on the surface of the lithography mask after the lithography mask is manufactured.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: August 24, 2010
    Assignee: Hoya Corporation
    Inventors: Masao Ushida, Megumi Takeuchi, Osamu Suzuki, Minoru Sakamoto
  • Patent number: 7611808
    Abstract: A halftone type phase shift mask having a semitranslucent film pattern and a shielding film pattern provided on a transparent substrate in this order is constituted in such a manner that each of the reflectances of the transparent substrate, the semitranslucent film pattern and the shielding film pattern for an inspecting light represents a difference which can detect the semitranslucent film pattern and the shielding film pattern based on a reflected light generated when the inspecting light is irradiated on the mask.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: November 3, 2009
    Assignee: Hoya Corporation
    Inventors: Masao Ushida, Minoru Sakamoto, Naoki Nishida
  • Publication number: 20090233182
    Abstract: It is provided a photomask blank that has good flatness when a light-shielding film is patterned and hence can provide a good mask pattern accuracy and a good pattern transfer accuracy, and a method of producing a photomask. A photomask blank of the present invention includes a light-shielding film containing at least chromium on a light-transmitting substrate. The light-shielding film is formed so as to cause a desired film stress in the direction opposite to that of a change in the film stress that is anticipated to be caused in the light-shielding film by heat treatment according to a resist film formed on the light-shielding film. A photomask is produced by patterning the light-shielding film of the photomask blank by dry etching.
    Type: Application
    Filed: September 29, 2006
    Publication date: September 17, 2009
    Applicant: HOYA CORPORATION
    Inventors: Takeyuki Yamada, Yasushi Okubo, Masao Ushida, Hiroyuki Iwashita
  • Publication number: 20070134568
    Abstract: A halftone type phase shift mask having a semitranslucent film pattern and a shielding film pattern provided on a transparent substrate in this order is constituted in such a manner that each of the reflectances of the transparent substrate, the semitranslucent film pattern and the shielding film pattern for an inspecting light represents a difference which can detect the semitranslucent film pattern and the shielding film pattern based on a reflected light generated when the inspecting light is irradiated on the mask.
    Type: Application
    Filed: December 21, 2006
    Publication date: June 14, 2007
    Inventors: Masao Ushida, Minoru Sakamoto, Naoki Nishida
  • Patent number: 7217481
    Abstract: In obtaining a photomask blank 1 by disposing a sputtering target in a vacuum chamber and forming thin films 3, 4, and 5 with a three-layer construction of CrN/CrC/CrON over a transparent substrate 2 by reactive sputtering, the thin films are formed in a mixed gas atmosphere containing helium, and the helium gas flux in the mixed gas is controlled such that the crystal grain diameter of the CrC thin film, which is the thickest film, will be 3 to 7 nm. This yields a photomask blank having thin films with low film stress, having good film quality, and which can be produced at a high yield in mass production.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: May 15, 2007
    Assignee: Hoya Corporation
    Inventors: Masaru Mitsui, Haruhiko Yamagata, Masao Ushida
  • Patent number: 7166392
    Abstract: A halftone type phase shift mask having a semitranslucent film pattern and a shielding film pattern provided on a transparent substrate in this order is constituted in such a manner that each of the reflectances of the transparent substrate, the semitranslucent film pattern and the shielding film pattern for an inspecting light represents a difference which can detect the semitranslucent film pattern and the shielding film pattern based on a reflected light generated when the inspecting light is irradiated on the mask.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: January 23, 2007
    Assignee: Hoya Corporation
    Inventors: Masao Ushida, Minoru Sakamoto, Naoki Nishida
  • Publication number: 20050250018
    Abstract: A lithography mask blank used as a material for producing a lithography mask includes at least one thin film which is formed on a substrate and has a desired function. The blank has a nitrogen-containing thin film as the above-mentioned thin film and an ammonium ion production preventing layer for preventing production of ammonium ions, which is formed on the nitrogen-containing thin film or at least at a surface portion of the nitrogen-containing thin film and which is exposed on the surface of the lithography mask after the lithography mask is manufactured.
    Type: Application
    Filed: December 24, 2003
    Publication date: November 10, 2005
    Inventors: Masao Ushida, Megumi Takeuchi, Osamu Suzuki, Minoru Sakamoto
  • Publication number: 20050142463
    Abstract: In obtaining a photomask blank 1 by disposing a sputtering target in a vacuum chamber and forming thin films 3, 4, and 5 with a three-layer construction of CrN/CrC/CrON over a transparent substrate 2 by reactive sputtering, the thin films are formed in a mixed gas atmosphere containing helium, and the helium gas flux in the mixed gas is controlled such that the crystal grain diameter of the CrC thin film, which is the thickest film, will be 3 to 7 nm. This yields a photomask blank having thin films with low film stress, having good film quality, and which can be produced at a high yield in mass production.
    Type: Application
    Filed: February 23, 2005
    Publication date: June 30, 2005
    Applicant: Hoya Corporation
    Inventors: Masaru Mitsui, Haruhiko Yamagata, Masao Ushida
  • Patent number: 6899979
    Abstract: In obtaining a photomask blank 1 by disposing a sputtering target in a vacuum chamber and forming thin films 3, 4, and 5 with a three-layer construction of CrN/CrC/CrON over a transparent substrate 2 by reactive sputtering, the thin films are formed in a mixed gas atmosphere containing helium, and the helium gas flux in the mixed gas is controlled such that the crystal grain diameter of the CrC thin film, which is the thickest film, will be 3 to 7 nm. This yields a photomask blank having thin films with low film stress, having good film quality, and which can be produced at a high yield in mass production.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: May 31, 2005
    Assignee: Hoyo Corporation
    Inventors: Masaru Mitsui, Haruhiko Yamagata, Masao Ushida
  • Publication number: 20030219654
    Abstract: A halftone type phase shift mask having a semitranslucent film pattern and a shielding film pattern provided on a transparent substrate in this order is constituted in such a manner that each of the reflectances of the transparent substrate, the semitranslucent film pattern and the shielding film pattern for an inspecting light represents a difference which can detect the semitranslucent film pattern and the shielding film pattern based on a reflected light generated when the inspecting light is irradiated on the mask.
    Type: Application
    Filed: February 28, 2003
    Publication date: November 27, 2003
    Applicant: HOYA CORPORATION
    Inventors: Masao Ushida, Minoru Sakamoto, Naoki Nishida
  • Patent number: 4696877
    Abstract: In a photo-mask blank comprising a transparent substrate member and a shading layer of chromium covered on a principal surface of the substrate member, the shading layer has a first portion adjacent the principal surface and etched at a first etch rate and a second portion farther from the principal surface than the first portion and etched at a second etch rate lower than the first etch rate. For this purpose, nitrogen is dispersed so that the first portion becomes rich in nitrogen as compared with the second portion. Alternatively, carbon is dispersed so that the first portion becomes scarce in carbon relative to the second portion. The first portion may include nitrogen. The substrate member may comprise a transparent flat plate and a transparent conductive layer coated on the flat plate. The photo-mask blank is processed into a photo-mask through an etching process.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: September 29, 1987
    Assignee: Hoya Corporation
    Inventors: Shigekazu Matsui, Kenichi Kagaya, Masao Ushida, Kouichi Maruyama
  • Patent number: 4563407
    Abstract: In a photo-mask blank comprising a transparent substrate member and a shading layer of chromium covered on a principal surface of the substrate member, the shading layer has a first portion adjacent the principal surface and etched at a first etch rate and a second portion farther from the principal surface than the first portion and etched at a second etch rate lower than the first etch rate. For this purpose, nitrogen is dispersed so that the first portion becomes rich in nitrogen as compared with the second portion. Alternatively, carbon is dispersed so that the first portion becomes scarce in carbon relative to the second portion. The first portion may include nitrogen. The substrate member may comprise a transparent flat plate and a transparent conductive layer coated on the flat plate. The photo-mask blank is processed into a photo-mask through an etching process.
    Type: Grant
    Filed: November 15, 1983
    Date of Patent: January 7, 1986
    Assignee: Hoya Corporation
    Inventors: Shigekazu Matsui, Kenichi Kagaya, Masao Ushida, Kouichi Maruyama
  • Patent number: D543160
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: May 22, 2007
    Assignee: Hoya Corporation
    Inventors: Masaru Mitsui, Shigekazu Matsui, Masao Ushida, Osamu Nagarekawa
  • Patent number: D568839
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: May 13, 2008
    Assignee: Hoya Corporation
    Inventors: Masaru Mitsui, Shigekazu Matsui, Masao Ushida, Osamu Nagarekawa