Title:
ELECTRON GUN
Document Type and Number:
Japanese Patent JP2018147871
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a high-brightness electron gun cathode with a low work function.SOLUTION: An electron gun is constructed by lanthanum or cerium atom and a cathode material in which a carbon atom and a boron atom are combined in a predetermined adjacent distance. In a work function of the electron gun cathode, the work function of LaB6 or CeB6 is 2.7 eV. However, the work function can be reduced to 1.7 eV or less by diffusing, mixing, or combining the carbon atom, and a brightness of 10A/cmsteradian can be achieved with 50kV under a low temperature operation of 1200°C or less. By reducing the work function, a high brightness low temperature operation can be performed. A life of the electron gun is improved by preventing the boron atom and the carbon atom from being burned due to an oxygen concentration at high vacuum of 10pascal or more. Furthermore, by adhering a supply material of the carbon atom to the cathode material or a heater as a supply source, the life can be further improved.SELECTED DRAWING: Figure 1
Inventors:
YASUDA HIROSHI
DAIKYO YOSHIHISA
MURATA HIDEKAZU
DAIKYO YOSHIHISA
MURATA HIDEKAZU
Application Number:
JP2017101230A
Publication Date:
September 20, 2018
Filing Date:
May 22, 2017
Export Citation:
Assignee:
PARAM CO LTD
International Classes:
H01J1/148; G03F7/20; H01J37/06; H01L21/027
Attorney, Agent or Firm:
Patent Corporation yki International Patent Office