Detectors
24
VEGA 3 SEM
scintillator to the cathode of the photo-multiplier. They are then processed in the same way
as the signal coming from the secondary electrons.
The BSE detector is manufactured in an R-BSE (Retractable BSE) version. This modification
allows the retraction of the detector from under the pole piece position if the detector is not
used. This enables the specimens to be moved as close as possible to the objective when
viewed by other detectors.
6.4
CL detector
The detector works in high as well as low vacuum.
The cathodoluminescence detector is available in two versions depending on the wavelength
range of the detected light: 350 – 650 nm range (mainly visible and near UV light) or 185 –
850 nm range (UV, visible and near IR light). The first version is made either as a stand-
alone detector or exchange CL / BSE detector.
The IR camera (Chamber View) must be switched off during operation of the CL detector.
6.4.1
Exchange of CL for BSE lightguide
(Only available in exchange CL / BSE of 350 – 650 nm range version)
1.
Fully retract the current detector (i.e. it is close to the chamber wall, not under the
column).
2.
Put on gloves and open the chamber. Rotate the light guide by hand around its axis
by about 30 degrees.
3.
Move the current lightguide horizontally in the direction of its axis towards the
objective until it is released.
4.
Insert the new lightguide in exactly the opposite way: rotated by about 30 degrees
from its working position, move it in the direction of its axis horizontally towards the
photomultiplier until the stop.
5.
Rotate the new lightguide by hand to its fixed position.
6.
Return the detector carefully to its working position using the retraction mechanism
and observe whether the new lightguide sits well and does not hit the objective.
