Patents by Inventor Keiichi Ohtsuka

Keiichi Ohtsuka 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).

  • Crystalline forms of pyrimidine nucleoside derivative
    Patent number: 6908906
    Abstract: The present invention provides crystalline forms and compositions thereof, of a pyrimidine nucleoside derivative of formula (I) having anti-tumour activity, wherein formula (I) is:
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: June 21, 2005
    Assignee: Sankyo Company, Limited
    Inventors: Takashi Takita, Keiichi Ohtsuka, Eiji Numagami, Susumu Harashima
  • Crystalline forms of pyrimidine nucleoside derivative
    Publication number: 20040053883
    Abstract: The present invention provides crystalline forms and compositions thereof, of a pyrimidine nucleoside derivative of formula (I) having anti-tumour activity, wherein formula (I) is: 1
    Type: Application
    Filed: August 7, 2003
    Publication date: March 18, 2004
    Applicant: SANKYO COMPANY, LIMITED
    Inventors: Takashi Takita, Keiichi Ohtsuka, Eiji Numagami, Susumu Harashima
  • Chemical vapor deposition process for depositing tungsten
    Patent number: 6156382
    Abstract: A multiple step chemical vapor deposition process for depositing a tungsten layer on a substrate. A first step of the deposition process includes a nucleation step in which WF.sub.6 and SiH.sub.4 are introduced into a deposition chamber. Next, the flow of WF.sub.6 and SiH.sub.4 are stopped and diborane is introduced into the chamber for between 5-25 seconds. Finally, during a bulk deposition step, the WF.sub.6 is reintroduced into the chamber along with H.sub.2 and B.sub.2 H.sub.6 flows to deposit a tungsten layer on the substrate. In a preferred embodiment, the bulk deposition step also introduces nitrogen into the process gas.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: December 5, 2000
    Assignee: Applied Materials, Inc.
    Inventors: Ravi Rajagopalan, Steve Ghanayem, Manabu Yamazaki, Keiichi Ohtsuka, Yuji Maeda