Analysis of the extended defects in 3C-SiC.pdf - Nelson Mandela ...

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The nuclear stopping power Sn is thus given by these dimensionless parameters as
d
which is a function of ε only. The electronic stopping power Se is given by,
d
d
d
n
e
k
1
2
1 2 1 2
3 2
1 0.
0793Z1
Z 2 ( M 1 M 2 )
6
with k Z1
2 3 2 3 3 4 3 2 1 2
( Z1
Z 2 ) M 1 M 2
(3.12)
(3.13)
A universal curve cannot be obtained for the electronic stopping power since k
depends on the colliding atoms. Fig. 3.1 shows the electronic stopping power plotted
for two values of k being 1.5 and 0.15. The straight line indicates the dependence on
velocity.
Fig. 3.2. Reduced range-energy plots for various values of the electronic stopping
parameter k (from Carter et al. (1976))
The average total path length ρ is then given by,
0
d { S n ( )
S e ( )}
(3.14)