Focused A special type of ATEM also allows energy ı NanOR
electron beam filtered fixed beam images with in-column or 0
i _ post-column imaging filters (5). This technique 3 Mal
ag Energy dispersive . . .
X-ray detector uses precisely the inelastically scattered electrons .
; ; with their element-specific energy losses. Th“
ae X-ray microanalysis pes
Specimen gre
Viewing /N Electron
screen 7A microdiffraction
Electron energy
1 loss spectrometry
Machen
RM. 1
spectrometer Detector
Figure 1: Schematic arrangement of the analytical
components of an ATEM
ee All analytical information is generated by
ld ay scattering processes of the primary electrons. The
A 34 elacıron DE interaction of the electron beam with sample
A atoms is schematically illustrated in Figure 2. In
conventional TEM the imaging process is
primarily based on the contrast arising from both
wo, the partial elimination and the interference of the
re Te elastically scattered electrons. When inelastic jy. |
To da } scattering occurs the incident electrons undergo wich (082
CME ie dea element-specific energy losses AE, which can be
specific used for chemical analysis by electron energy loss
we spectroscopy. Simultaneously, an electron is flees
ejected with AE from an inner electron shell. In a diagram ı
second step this gap is occupied by an electron
5. from an outer shell, and the energy difference is Four nett
) N ki 3 compensated by an element-specific X-ray mew
glections with radiation which can be analyzed by energy frog
glamentspetific . . CC.
anorgy loss AE dispersive X-ray spectroscopy which wa
vr RCatlele
BleCifons
Figure 2: Interaction of the primary electron
beam with sample atoms
12