Patents by Inventor Koichi Ohto

Koichi Ohto 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).

  • Publication number: 20030209738
    Abstract: In a semiconductor device, an insulating interlayer having a groove is formed on an insulating underlayer. A silicon-including metal layer including no metal silicide is buried in the groove. A metal diffusion barrier layer is formed on the silicon-including metal layer and the insulating interlayer.
    Type: Application
    Filed: October 28, 2002
    Publication date: November 13, 2003
    Applicant: NEC CORPORATION
    Inventors: Koichi Ohto, Toshiyuki Takewaki, Tatsuya Usami, Nobuyuki Yamanishi
  • Publication number: 20030155657
    Abstract: A manufacturing method of a semiconductor device including a step of forming a via hole in an insulation layer including an organic low dielectric film, such as MSQ, SiC, and SiCN, and then embedding a wiring material in the via hole through a barrier metal. According to this method, a plasma treatment is performed after the via hole is formed and before the barrier metal is deposited, using a He/H2 gas capable of replacing groups (methyl groups) made of organic constituents and covering the surface of the exposed organic low dielectric film (MSQ) with hydrogen, or a He gas capable decomposing the groups (methyl groups) without removing organic low dielectric molecules. As a result, the surface of the low dielectric film (MSQ) is reformed to be hydrophilic and adhesion to the barrier metal is hence improved, thereby making it possible to prevent the occurrence of separation of the barrier metal and scratches.
    Type: Application
    Filed: February 13, 2003
    Publication date: August 21, 2003
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Takashi Tonegawa, Koji Arita, Tatsuya Usami, Noboru Morita, Koichi Ohto, Yoichi Sasaki, Sadayuki Ohnishi, Ryohei Kitao
  • Publication number: 20020197865
    Abstract: A method for fabricating a semiconductor device wherein an interconnect made of copper overlying a substrate is pretreated at a specified temperature, for example, at 300° C. or less; and a dielectric film is formed on the copper at a temperature higher than that of the pretreatment. In accordance with the present invention, the adhesion between the copper and the dielectric film is improved by conducting the pretreatment of the dielectric film for reducing an oxide layer of the copper surface, and the agglomeration of the copper can be prevented by the pretreatment.
    Type: Application
    Filed: August 6, 2002
    Publication date: December 26, 2002
    Applicant: NEC CORPORATION
    Inventor: Koichi Ohto
  • Publication number: 20020155702
    Abstract: In order to provide a manufacturing method of a semiconductor device which can improve the interconnection lifetime, while controlling the increase in resistance thereof, and, in addition, can raise the manufacturing stability; by applying a plasma treatment to the surface of a copper interconnection 17 with a source gas comprising a nitrogen element being used, a copper nitride layer 24 is formed, and thereafter a silicon nitride film 18 is formed. Hereat, under the copper nitride layer 24, a thin copper silicide layer 25 is formed.
    Type: Application
    Filed: February 11, 2002
    Publication date: October 24, 2002
    Applicant: NEC CORPORATION
    Inventors: Hidemitsu Aoki, Hiroaki Tomimori, Norio Okada, Tatsuya Usami, Koichi Ohto, Takamasa Tanikuni
  • Patent number: 6335277
    Abstract: A method for forming a titanium nitride film of an excellent quality on a semiconductor substrate at a low temperature is achieved. With a heated semiconductor substrate on a susceptor held at a temperature of about 500° C., titanium tetrachloride and ammonia are introduced into a reactor to carry out the deposition of the titanium nitride film. After the deposition is completed, the semiconductor substrate within the reactor is continuously held at a temperature of 500° C. After a low pressure mercury lamp is turned on, while the inner part of the reactor is irradiated with ultraviolet rays with a wavelength of 170-280 nm emitted from the lamp, an ammonia gas is introduced, with the flow rate adjusted to about 1000 sccm, into the reactor held at a pressure of about 10 Torr to carry out annealing in an ammonia atmosphere for about 60 seconds.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: January 1, 2002
    Assignee: NEC Corporation
    Inventor: Koichi Ohto
  • Publication number: 20010054765
    Abstract: In a semiconductor device, an interlevel insulating film formed between a Cu interconnection, formed by damascene, and an upper metal interconnection layer on it has a multilayered structure made up of a Cu diffusion preventive insulating layer and another insulating film. The Cu diffusion preventive insulating layer has a multilayered structure made up of not less than two layers. A method for manufacturing the semiconductor device is also disclosed.
    Type: Application
    Filed: June 19, 2001
    Publication date: December 27, 2001
    Applicant: NEC Corporation
    Inventors: Koichi Ohto, Takayuki Matsui
  • Publication number: 20010047759
    Abstract: To provide a plasma CVD apparatus for forming a silicon nitride film and a fluorine-containing silicon oxide film in one and the same chamber, in which a NH3 gas pipeline for introducing NH3 gas as a part of raw material gases of the silicon nitride film and a SiF4 gas pipeline for introducing SiF4 gas as a part of the raw material gases of the fluorine-containing silicon oxide film are separately connected to an upper electrode also functioning as a shower head.
    Type: Application
    Filed: February 22, 2001
    Publication date: December 6, 2001
    Inventors: Takayuki Matsui, Koichi Ohto, Tatsuya Usami, Yoshiaki Tsuchiya, Shigeo Ishikawa
  • Publication number: 20010035241
    Abstract: A method for forming a titanium nitride film of an excellent quality on a semiconductor substrate at a low temperature is achieved. With a heated semiconductor substrate on a susceptor held at a temperature of about 500° C., titanium tetrachloride and ammonia are introduced into a reactor to carry out the deposition of the titanium nitride film. After the deposition is completed, the semiconductor substrate within the reactor is continuously held at a temperature of 500° C. After a low pressure mercury lamp is turned on, while the inner part of the reactor is irradiated with ultraviolet rays with a wavelength of 170-280 nm emitted from the lamp, an ammonia gas is introduced, with the flow rate adjusted to about 1000 sccm, into the reactor held at a pressure of about 10 Torr to carry out annealing in an ammonia atmosphere for about 60 seconds.
    Type: Application
    Filed: May 26, 1999
    Publication date: November 1, 2001
    Inventor: KOICHI OHTO
  • Publication number: 20010003064
    Abstract: A method for fabricating a semiconductor device wherein an interconnect made of copper overlying a substrate is pretreated at a specified temperature, for example, at 300° C. or less; and a dielectric film is formed on the copper at a temperature higher than that of the pretreatment. In accordance with the present invention, the adhesion between the copper and the dielectric film is improved by conducting the pretreatment of the dielectric film for reducing an oxide layer of the copper surface, and the agglomeration of the copper can be prevented by the pretreatment.
    Type: Application
    Filed: December 4, 2000
    Publication date: June 7, 2001
    Applicant: NEC CORPORATION
    Inventor: Koichi Ohto