Title:
CATHODE SELECTING METHOD AND ELECTRON BEAM DRAWING APPARATUS
Document Type and Number:
Japanese Patent JP2016225358
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a method of selecting a cathode that does not cause abnormality in the peripheral portion of an electron emission surface.SOLUTION: The method comprises a step S110 of using a measurement target cathode whose electron emission surface is limited to a flat surface by a cover member, in the state where the temperature of the cathode to be measured is maintained at a preset temperature and an acceleration voltage is applied between the measurement target cathode and an anode electrode, adjusting a bias voltage applied to the Wehnelt electrode, and starting the operation of the measurement target cathode in the temperature limit region, a step S112 of controlling the bias voltage so as to maintain the value of an emission current when the operation of the measurement target cathode is started for a predetermined period, a step S114 of judging whether or not the variation amount of the bias voltage during a predetermined period is smaller than a preset threshold value, and a step S116 of selecting the measurement target cathode as a usable cathode when the variation amount of the bias voltage when using the measurement target cathode is smaller than the threshold as a result of the determination.SELECTED DRAWING: Figure 7
Inventors:
SAITO KENICHI
TATEMICHI YUSUKE
TATEMICHI YUSUKE
Application Number:
JP2015107562A
Publication Date:
December 28, 2016
Filing Date:
May 27, 2015
Export Citation:
Assignee:
NUFLARE TECHNOLOGY INC
International Classes:
H01L21/027; G03F7/20; H01J1/15; H01J9/04; H01J37/06; H01J37/305
Attorney, Agent or Firm:
Tetsuma Ikegami
Akira Sudo
Mitsuyuki Matsuyama
Akira Sudo
Mitsuyuki Matsuyama
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