Patents by Inventor Shigeo Nagao

Shigeo Nagao 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: 5250468
    Abstract: The method of forming an interlayer insulating film insulating first and second layers of conductor patterns in a semiconductor device includes the steps of preparing a reaction gas including at least ozone and silicon alkoxide, wherein the ratio of ozone with respect to silicon alkoxide is adjusted to be not less than 5 within the reaction gas, and forming an insulating film by CVD reacting the reaction gas at atmospheric pressure at the temperature of 350.degree. C.- 450.degree. C., whereupon the interlayer insulating film includes at least the insulating film formed by atmospheric pressure CVD reaction.
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: October 5, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masazumi Matsuura, Hideo Kotani, Atsuhiro Fujii, Shigeo Nagao, Hideki Genjo
  • Patent number: 5215935
    Abstract: A method of forming a isolation region in a semiconductor device includes the steps of forming an underlying oxide film on a semiconductor substrate, forming a first polysilicon layer on the underlying oxide film, forming a silicon nitride film on the first polysilicon layer, patterning the silicon nitride film such that the silicon nitride film is left only on a circuit element region of the substrate at which a circuit element is to be formed, depositing selectively a second polysilicon layer by vapor deposition on regions of the first polysilicon layer which are exposed by patterning, and forming isolation regions of silicon oxide by thermally oxidizing at least the second and the first polysilicon layers using the patterned nitride film as a mask.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: June 1, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Shigeo Nagao
  • Patent number: 5132774
    Abstract: The method of forming an interlayer insulating film insulating first and second layers of conductor patterns in a semiconductor device includes the steps of preparing a reaction gas including at least ozone and silicon alkoxide, wherein the ratio of ozone with respect to silicon alkoxide is adjusted to be not less than 5 within the reaction gas, and forming an insulating film by CVD reacting the reaction gas at atmospheric pressure at the temperature of 350.degree. C.-450.degree. C., whereupon the interlayer insulating film includes at least the insulating film formed by atmospheric pressure CVD reaction.
    Type: Grant
    Filed: November 28, 1990
    Date of Patent: July 21, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masazumi Matsuura, Hideo Kotani, Atsuhiro Fujii, Shigeo Nagao, Hideki Genjo
  • Patent number: 4996168
    Abstract: An improved method for manufacturing P type semiconductor device such as used for memories is disclosed. Channeling such as caused by an ion implantation process is prevented by adopting a diffusion method to diffuse boron (7) from a boron glass formed on a layer of polysilicon or silicon oxide on a semiconductor substrate. This method provides a semiconductor device with shallow P type impurity diffusion regions.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: February 26, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroji Ozaki, Shigeo Nagao