Patents by Inventor Kiyohito Tanno

Kiyohito Tanno 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).

  • CERIUM OXIDE ABRASIVE FOR POLISHING INSULATING FILMS FORMED ON SUBSTRATE AND METHODS FOR USING THE SAME
    Publication number: 20020016060
    Abstract: The invention relates to an abrasive containing a slurry of the following cerium oxide grains as dispersed in water:
    Type: Application
    Filed: December 30, 1997
    Publication date: February 7, 2002
    Inventors: JUN MATSUZAWA, YASUSHI KURATA, KIYOHITO TANNO, YOSHIO HONMA
  • Abrasive, method of polishing wafer, and method of producing semiconductor device
    Patent number: 6343976
    Abstract: To polish polishing target surfaces of SiO2 insulating films or the like at a high rate without scratching the surface, the present invention provides an abrasive comprising a slurry comprising a medium and dispersed therein at least one of i) cerium oxide particles constituted of at least two crystallites and having crystal grain boundaries or having a bulk density of not higher than 6.5 g/cm3 and ii) abrasive grains having pores. Also provided are a method of polishing a target member and a process for producing a semiconductor device which make use of this abrasive.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: February 5, 2002
    Assignee: Hitachi Chemical Company, Ltd.
    Inventors: Masato Yoshida, Toranosuke Ashizawa, Hiroki Terazaki, Yuuto Ootuki, Yasushi Kurata, Jun Matsuzawa, Kiyohito Tanno
  • Cerium oxide abrasive and method of polishing substrates
    Patent number: 6221118
    Abstract: This invention provides a cerium oxide abrasive with which the surfaces of substrates such as SiO2 insulating films can be polished at a high rate without causing scratches. The abrasive of the present invention comprises a slurry comprising cerium oxide particles whose primary particles have a diameter of from 10 nm to 600 nm and a median diameter of from 30 nm to 250 nm and slurry particles have a median diameter of from 150 nm to 600 nm and a maximum diameter of 3,000 nm or smaller, the cerium oxide particles being dispersed in a medium.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: April 24, 2001
    Assignee: Hitachi Chemical Company, Ltd.
    Inventors: Masato Yoshida, Toranosuke Ashizawa, Hiroki Terazaki, Yasushi Kurata, Jun Matsuzawa, Kiyohito Tanno, Yuuto Ootuki