Patents by Inventor Makoto Nakase

Makoto Nakase 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).

  • Method of forming a mask on a semiconductor substrate via photosensitive resin deposition, ammonia treatment and selective silylation
    Patent number: 5407786
    Abstract: A photosensitive organic resin layer is formed on a semiconductor substrate. The resin layer is treated with ammonia before or after the resin layer is exposed. Then, the exposed organic resin layer is easily silylated. Due to the ammonia treatment, non-exposed portions of the organic resin layer is hardly silylated so that a high aspect ratio of patterning is realized.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: April 18, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinishi Ito, Haruo Okano, Makoto Nakase
  • Exposure mask, method of manufacturing the same, and exposure method using the same
    Patent number: 5358808
    Abstract: An exposure mask for lithography, a method of manufacturing the same, and an exposure method using the same are disclosed. A light-transmitting opening of the exposure mask has a main light-transmitting region located in the middle of the opening and having a first optical path length, and phase shift regions adjacent to a light-shielding layer and having a second optical path length, different from the first optical path length. Light transmitted through each phase shift region interferes with light transmitted through the main light-transmitting region at the edges of the light-transmitting opening, thus enabling a sharp photo-intensity distribution of total transmitted light to be obtained. As a result, the resolution of the exposure mask is improved.
    Type: Grant
    Filed: July 21, 1993
    Date of Patent: October 25, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Nitayama, Makoto Nakase, Kouji Hishimoto, Hirotsugu Wada
  • Exposure mask, method of manufacturing the same, and exposure method using the same
    Patent number: 5234780
    Abstract: An exposure mask for lithography, a method of manufacturing the same, and an exposure method using the same are disclosed. A light-transmitting opening of the exposure mask has a main light-transmitting region located in the middle of the opening and having a first optical path length, and phase shift regions adjacent to a light-shielding layer and having a second optical path length, different from the first optical path length. Light transmitted through each phase shift region interferes with light transmitted through the main light-transmitting region at the edges of the light-transmitting opening, thus enabling a sharp photo-intensity distribution of total transmitted light to be obtained. As a result, the resolution of the exposure mask is improved.
    Type: Grant
    Filed: January 18, 1990
    Date of Patent: August 10, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Nitayama, Makoto Nakase, Kouji Hashimoto, Hirotsugu Wada
  • Pattern forming method utilizing material with photoresist film underlayer and contrast enhancement overlayer containing photosensitive diazonium salt
    Patent number: 5188924
    Abstract: A pattern forming method, comprising the steps of providing a resist film on a substrate; providing a photosensitive film containing a photosensitive diazonium salt on the resist film; and then subjecting the resultant composite to pattern exposure by use of a light to which both of the resist film and the photosensitive diazonium salt are sensitive, can employ a composition for pattern formation which comprises a photosensitive diazonium salt, a resin binder and a solvent. By this method, a minute pattern of 1 .mu.m or less can be formed, utilizing effectively the UV-ray exposure technique of the prior art, with good dimensional precision and stability.
    Type: Grant
    Filed: October 16, 1991
    Date of Patent: February 23, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kunihiro Ikari, deceased, Hirokazu Niki, Makoto Nakase, Toshiaki Shinozaki