Patents by Inventor Tiharu Kato

Tiharu Kato 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: 4988609
    Abstract: In a patterning method according to this invention, a surface region of a resist layer is solution-retarded by a developer, and, then, the resist layer is patterned. Therefore, a desired shape of a side wall of the resist layer may be obtained by varying a solubility of the resist layer, with the result that a resist pattern with the side wall orthogonal to a surface of the substrate or the overhung side may be formed.
    Type: Grant
    Filed: June 13, 1988
    Date of Patent: January 29, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidetsuna Hashimoto, Tiharu Kato, Hitoshi Tsuji
  • Patent number: 4914006
    Abstract: A positive resist developer comprising a solution containing a quaternary ammonium hydroxide, a cationic surfactant and a nonionic surfactant.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: April 3, 1990
    Assignees: Kabushiki Kaisha Toshiba, Kanto Chemical Co., Ltd.
    Inventors: Tiharu Kato, Kazuyuki Saito, Norio Ishikawa, Kiyoto Mori
  • Patent number: 4792534
    Abstract: A method of manufacturing a semiconductor device having a submicron pattern. A p-type semiconductor layer is formed on an n-type semiconductor substrate. Insulating films are formed on the p-type semiconductor layer. A first mask layer, such as an aluminum layer having an etching rate different from that of the insulating films, is formed on the insulating films. A second mask layer having an etching rate different from that of the first mask layer, is formed on the first mask layer. The second mask layer is patterned. A coating film having an etching rate different from that of the first insulating film, is formed on the resultant structure. The coating film is etched to be left on a side wall of the patterned second mask layer. The first mask layer is patterned, using the residual coating film and the patterned second mask layer as masks, and a pattern finer than that of the resist is formed in the first mask layer.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: December 20, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Tsuji, Tiharu Kato, Kiyoshi Takaoki
  • Patent number: 4525523
    Abstract: There is proposed a negative-working photoresist coating composition of an improved resolution, which comprises a cyclized polyisoprene having a weight-average molecular weight of 10,000 to 100,000 and a molecular weight distribution of not more than 1.9, an organic solvent of the cyclized polyisoprene, and a bisazido compound as a crosslinking agent.
    Type: Grant
    Filed: August 26, 1983
    Date of Patent: June 25, 1985
    Assignees: Kanto Chemical Co., Inc., Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hatsuo Nakamura, Tiharu Kato, Toshio Yonezawa, Shigeo Koguchi, Kiyoto Mori, Masahiko Igarashi
  • Patent number: 4461825
    Abstract: An improved method of forming a photoresist pattern in the photoengraving process. In the photoengraving process, after forming a photoresist layer, a non-photosensitive organic layer containing cyclized polyisoprene rubber as the major constituent is formed thereover. The organic layer is covered with a mask. The photoresist layer is selectively exposed to light through the organic layer. After developing and removing the organic layer, or together with the organic layer, the photoresist layer is developed.
    Type: Grant
    Filed: September 26, 1983
    Date of Patent: July 24, 1984
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Tiharu Kato, Hatsuo Nakamura, Shigeo Koguchi, Toshio Yonezawa, Toshihiro Abe