2 ELPHY Plus and ELPHY Quantum Hardware Guide
10
2.1.4 Electronic Beam Blanker Control Unit
The beam blanker control unit consists of a high voltage power supply
and associated control electronics. It accepts a TTL signal from the
ELPHY Quantum or ELPHY Plus to switch the high voltage on or
off. Typical output of the high voltage is 200 volts. The high voltage
is applied to the beam blanker hardware plates to deflect the electron
beam.
Zeiss FEG SEM systems will be supplied with a 19in. rack system.
This unit has 8kV input and output and requires installation by Zeiss.
2.1.5 Beam Blanker Hardware
The beam blanker hardware is install on the SEM column by either
Raith or the SEM manufacture. Further information should be
obtained from the SEM manufacture if installed by them.
Basic hardware consists of two parallel plates, one connected to
ground and the other to the high voltage. Some systems have
mechanical adjustment for positioning the plates concentric to the
electron beam.
Figure 3
Beam blanker schematic.
+ V
e
-
Spray Aperture
V applied
Filament
V off
Electrons entering the beam
blanker will be deflected when a
voltage +V is applied. A spray
aperture further down the
column prevents the electrons
from reaching the surface of the
sample.
When V=0 the electrons are
allowed to pass through the
spray aperture and therefore to
reach the sample surface.
2.1.6 Universal Sample Holder
The universal sample holder is a convenient way to mount small chip
size samples. A simple clamping system holds the sample in place.
There is room to have several samples and a calibration sample, e.g.
Chessy. An inbuilt Faraday cup enables the user to measure the total
To Next Page
Loading...