![background image](http://html.mh-extra.com/html/zeiss/crossbeam-340/crossbeam-340_instruction-manual_927492037.webp)
PK=aÉëÅêáéíáçå
fåëíêìÅíáçå=j~åì~ä=`êçëëÄÉ~ã=PQM
=
ÉåMOE`loF
=PT=çÑ=NPQ
mêáåÅáéäÉ=çÑ=çéÉê~íáçå
1
In-lens SE detector
2
Beam path
3
Objective lens
4
Specimen
At an acceleration voltage of maximum 20 kV,
the electrons of the primary electron beam are
additionally accelerated by 8 kV, the beam
booster voltage.
To ensure that the electrons reach the speci-
men surface (
4
) with the energy set as acceler-
ation voltage, an electrostatic field is generated
at the end of the objective lens by 8 kV. This
electrostatic field acts as acceleration field to
the SE generated on the specimen surface.
At the In-lens SE detector the electrons hit a
scintillator. This generates a flash of light that is led out of the beam path by means of a lightguide
onto a photomultiplier. The multiplier converts the light information into an electronic signal, which
can be displayed on the monitor.
IMPORTANT
The In-lens SE detector can be used up to an acceleration voltage of 20 kV.
At higher acceleration voltages, the beam booster and thus the field of the electrostatic
lens are switched off. This reduces the efficiency of the In-lens detector.
The efficiency of the In-lens SE detector is mainly determined by the electric field of the electro-
static lens, which is decreasing exponentially with the distance.
Thus, the working distance (WD) is one of the most important factors affecting the signal-to-noise
ratio of the In-lens detector.
As the tilt angle of the specimen surface affects the emission angle of the electrons, you should
avoid strong specimen tilting.
3.3.4.2. SE2 detector
The SE2 detector (
3
) is a Everhart-Thornley type detector. It detects SEs as well as BSEs.
Electrons moving to the detector are attracted by the collector grid (
2
) and directed to the scintil-
lator. The collector voltage can be varied in the range between -250 V and + 400 V. This collector
voltage generates an electrical field in front of the detector thus directing the low energy SEs to-
wards the scintillator.
Fig. 3.9: Schematics of In-lens SE detec-
tor
Summary of Contents for Crossbeam 340
Page 1: ...Crossbeam 340 Crossbeam workstation Instruction Manual ...
Page 24: ...OQ çÑ NPQ fåëíêìÅíáçå j åì ä êçëëÄÉ ã PQM ÉåMOE loF OK p ÑÉíó p ÑÉíó ÉèìáéãÉåí ...
Page 60: ...SM çÑ NPQ fåëíêìÅíáçå j åì ä êçëëÄÉ ã PQM ÉåMOE loF RK fåëí ää íáçå ...
Page 120: ...NOM çÑ NPQ fåëíêìÅíáçå j åì ä êçëëÄÉ ã PQM ÉåMOE loF UK qêçìÄäÉëÜççíáåÖ mçïÉê ÅáêÅìáí ...
Page 126: ...NOS çÑ NPQ fåëíêìÅíáçå j åì ä êçëëÄÉ ã PQM ÉåMOE loF NNK ÄÄêÉîá íáçåë ...
Page 130: ...NPM çÑ NPQ fåëíêìÅíáçå j åì ä êçëëÄÉ ã PQM ÉåMOE loF NPK aÉÅä ê íáçå çÑ ÅçåÑçêãáíó ...
Page 133: ......