Stereo Scan 440 - DCU

" Chapter 3 Advanced Operation 3-13
Figure 3.8(b) Taken at a slow scan speed
The abow shows a sample of Ceramic
3.5. Specimen Preparation
Specimens which are studied in the SEM can be divided into two main
categories, namely conductors and non-conductors. Factors to consider during
specimen preparation are given below:-
The size of the specimen must be reduced (if necessary) to fit the
available specimen holders and specimen stages, but there is often an
advantage in selecting an even smaller sample size for ease of
roservation.
2 The object must be able to withstand being in the high vacuum of the
SEM; it must not change its shape, and it must not outgas. A cold stage
may help here.
3, It should be clean, ie free of dust, oils and greases. (Their presence can
lead to charging and contamination effects.)
4. It may be treated to improve the secondary yield if this is low, eg coating
of the sample with gold.
s. Any disturbance in the surface structure caused by preparation
procedures should give rise to surface details which are too fme to be
resolved at the magnification used to record the images.
Stereoscan 440 Operator Manual