3.3Application of High Voltage
3.3.1Condition where the gun high voltage is applicable
You can apply high voltage when the HV display area on the control panel is blinking with yellow and blue colors. When the indication is blue, high voltage can not be applied. It will be in almost case because of vacuum degradation of specimen chamber or gun ion pumps. Also the specimen exchange chamber must be evacuated and the gate valve must be closed.
While high voltage is applied, the indication is shown in yellow color.
3.3.2Flashing
3.3.2.1 About flashing
Flashing is a procedure for removing gas molecules which have been adsorbed on the surface of the cathode (FE tip) in the electron gun.
Flashing is needed as follows.
(1) Flash once everyday before use
When the emission current becomes unstable, flash again.
(2) Flash once at the end of daily operation
On the next day, start operation without flashing. Flash if the emission current becomes unstable during operation.
3.3.2.2Flashing Procedure
Use the following procedures for flashing.
(1)Click the HV display area on the control panel. The HV control dialog window will open.
(2)Click the Flashing button on it. The Flashing execution dialog window will open.
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