DEFECTS IN METALS AND SIMULATION OF MECHANICAL ...

Fig. 3-6: Fraction Nv/n of surviving vacancies as a function of PKA energy (KEV) and of
Temperature (K) at 15 picoseconds
Fig. 3-6 shows the fraction of vacancies created out of the total number of atoms as a function of
temperature and PKA initial energy. The percentage of vacancies created at the end of the
simulation is increasing with the energy of the Primary knock-on Atom for both temperatures of
300 and 400 K, taking into consideration the effect of the temperature on the number of
vacancies created, we can see that the percentage of vacancies created is also an increasing
function of the temperature since for the same PKA energy but at a higher temperature of 400 K
a higher fraction of vacancies is created at the end of the cascade process. The effect of
temperature and PKA energy on the percentage of vacancies was also studied in other works by
K. Nordlund [ 34 ] and A. M. Rutherford and D M Duffy [ 39 ], Nordlund studied the relation
between the PKA energy and the number of defects on GaN and he showed that the number of
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