Scanning Electron Microscope
EM-30PLUS Operating Manual
27
After changing acceleration voltage, carry out alignment of e-gun and aperture Wobble
operation.
For the details, see [5.2.2 Setting Acceleration Voltage].
Vacuum Type (optional)
: It is a button for converting the vacuum state inside the chamber.
HIGH VACUUM: It indicates current state is at high vacuum or ready for high vacuum.
Keep the vacuum state of chamber inside at the level of below 10
-4
torr.
LOW VACUUM: It indicates current state is at low vacuum or ready for low vacuum.
It is mainly used to measure non-conductive solid specimens such as plastic, fiber, and
ceramics. Keep the vacuum state of chamber inside at the level of 10
-1
~10
-2
torr.
When using Low vacuum Mode, See [5.8 LV Mode(Low Vacuum Mode)-Optional].
Gun Vacuum: It indicates the vacuum state of the e-gun chamber.
Emission Current
: It indicates the value of Emission Current of electron beam.
Set the value of Emission Current by adjusting Filament Value and BIAS Value.
(Recommended Emission Current: 50±5uA)
If the value of Emission Current is indicated as 0 after adjusting Filament and BIAS values,
Filament is disconnected. Replace the Filament.
Filament Value
: It indicates the voltage value applied to Filament.
Adjust the Filament Value towards the green bar area(Saturation point area).
(Standard saturation point: about 75%(3/4) of the Filament bar)
* If you set the value over the saturation point(beyond the green bar area) and use the
equipment, lifespan of filament can be reduced.
* When e-gun is turned on, it is automatically set in the filament value used previously.