COLLECTOR
CATHODE
TARGET
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FIG. 6. I.
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Apparatus for measuring secondary emission
----- ___ __
!50/
E N E R G Y (ev)
K )O
L
t2
c0
1
I
i
300
200
loo
ENERGY LOS5 (me VI
0
J
200:
ENERG
Figure 5.12. Energy distribution of scaltcrcd clcctrons from an cthylcnc-covcrcd Rh(
Clpld surf-act at 300 K 1571.
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1 1 1)
-
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-A.- _- ___. - _
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1-o-
SPECTROSCOPY
SEE KINETIC ENERGY Eki,(eV)
SECONDARY-ELE CTRON-EMISSION
-.
W(111)
.
.
.
_
_
5145
_.
s
FIG. 3. S y m m e t r y - o r i e n t e d d i r e c t i o n a l s e c o n d a r y - e l e c t r o n e m i s s i o n normal to (a) W(lOO), 8) W(llO), and (c) W(111)
s u r f a c e s . The one-dimensional bulk bands and density of states D(E) along the associated symmetry lines are shown
for comparison. The SEE kinetic cncr~~ ELln (cV) 1s
’ referred to the \‘ac;Ium lcvcl &ti The positions of energy band-gap
features are indicated. The crosshatched peak at Ekill= 0 eV (a) is an csperimcntal artifact which appears in all spectra.
18
1000
Epo
E,_
2000
E, (ev)
FIG. 13-3-2. A typical plot of secondary clcctron yield J ris n function of the cncrgy of
the primary clcctrons E,,. Tlx numerical values of the yield shown hcrc m-c rcprcsentative of pure nxtals and many semiconductors , altl~ougl~ intcrrnctallic compounds and
insularws may have consitlcral~ly lli~licr yicltls (SW -rabk 13-52).
0
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.
d
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L
100 2 0 0 3 0 0 400
VOLTS
;A
The effect of angk of incidence
,
:
I
I
1
500
600.
’
on secondary emission
.
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Ni
] Ti
Al
Be
7
2 Ep, kc\’
b)
NaCl
Kl
1
Ti
Target
FIGURE 15.5
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i
I/
After acid etching
-
Before acid etching
200
400
600
800
1000
Priman/ electron energy (ev)
Figure 1. Secondary electron emission characteristics of Cu-Al-Mg alloys
in different processing procedures.
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a photomultiplicr (Rajchman type)
COLUMN
6V -xx)v 5-SOW
Mognetlc
Lens
Sample
Sample Current
\
Fig.Y.1. Schematic set-up of a scanning
electron microscope or microprobe
*-/ Incident electrons
( electron probe 1
- Choroctwistic X-ruys
Fig.V.6. Schematic overview of the pear-shaped volume probed bv different microprobe signals (electron and X-ray emission), when a primarv electroi barn is incident
on 3 solid sufrxe. Auger electrons originale from a depth df 5t:O /i, whereas the Xray information depth is 0.1 t10 pm with much less spatial resolution
I
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..