Patents by Inventor Hisao Nitta

Hisao Nitta 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: 10074506
    Abstract: A conventional method to process a tip fails to designate the dimension of the shape of the end of the tip, and so fails to obtain a tip having any desired diameter. Impurities may be attached to the tip. Based on a correlation between the voltage applied or the time during processing of the end of the tip and the diameter of the tip end, the applied voltage is controlled so as to obtain a desired diameter of the tip end for processing of the tip. This allows a sharpened tip made of a tungsten monocrystal thin wire to be manufactured to have any desired diameter in the range of 0.1 ?m or more and 2.0 ?m or less.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: September 11, 2018
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Takashi Ichimura, Hisao Nitta, Nobuyuki Sonobe, Boklae Cho, Hisaya Murakoshi
  • Publication number: 20150255240
    Abstract: A conventional method to process a tip fails to designate the dimension of the shape of the end of the tip, and so fails to obtain a tip having any desired diameter. Impurities may be attached to the tip. Based on a correlation between the voltage applied or the time during processing of the end of the tip and the diameter of the tip end, the applied voltage is controlled so as to obtain a desired diameter of the tip end for processing of the tip. This allows a sharpened tip made of a tungsten monocrystal thin wire to be manufactured to have any desired diameter in the range of 0.1 ?m or more and 2.0 ?m or less.
    Type: Application
    Filed: October 12, 2012
    Publication date: September 10, 2015
    Inventors: Takashi Ichimura, Hisao Nitta, Nobuyuki Sonobe, Boklae Cho, Hisaya Murakoshi
  • Patent number: 8766542
    Abstract: The disclosed charged particle beam apparatus includes a field-emission electron source including <310> single crystal of tungsten; a vacuum chamber having the electron source therein; an exhausting system for exhausting the vacuum chamber; a filament connected to the electron source to let flow a current through the electron source and thereby heat the electron source; a power supply for letting a current flow through the filament; an ammeter for measuring a total current emitted from the electron source; and a controlling unit for exercising control to cause the power supply to let a current flow through the filament when the total current measured periodically has become a predetermined ratio or less as compared with a total current from the electron source found immediately after first electron beam emission, or a total current from the electron beam found immediately after a current is let flow through the filament.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: July 1, 2014
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Boklae Cho, Shigeru Kokubo, Hisaya Murakoshi, Hisao Nitta
  • Publication number: 20130200788
    Abstract: The disclosed charged particle beam apparatus includes a field-emission electron source including <310> single crystal of tungsten; a vacuum chamber having the electron source therein; an exhausting system for exhausting the vacuum chamber; a filament connected to the electron source to let flow a current through the electron source and thereby heat the electron source; a power supply for letting a current flow through the filament; an ammeter for measuring a total current emitted from the electron source; and a controlling unit for exercising control to cause the power supply to let a current flow through the filament when the total current measured periodically has become a predetermined ratio or less as compared with a total current from the electron source found immediately after first electron beam emission, or a total current from the electron beam found immediately after a current is let flow through the filament.
    Type: Application
    Filed: January 19, 2011
    Publication date: August 8, 2013
    Applicant: HITACHI HIGH-TECHNOLOGIES CORPORATION
    Inventors: Boklae Cho, Shigeru Kokubo, Hisaya Murakoshi, Hisao Nitta