Patents by Inventor Kenichi Kagaya

Kenichi Kagaya 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).

  • Photo-mask blank comprising a shading layer having a variable etch rate
    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
  • Photo-mask blank comprising a shading layer having a variable etch rate
    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