Comparative molecular dynamics simulations of collision cascades in 2 elemental semiconductors and in 5 face-centered cubic metals were performed in order to explain how various material characteristics affected primary defect production during ion irradiation. By simulating 400eV to 10keV collision cascades, and comparing the results for different materials, the effect of mass, melting point, strength and crystal structure upon modification of the material by cascades was clarified. The results showed that the crystal structure had a large effect upon many aspects of damage production, while other material characteristics were of lesser overall importance. In all of the materials which were considered, the isolated point defects that were produced by the cascade were predominantly interstitials. In the case of semiconductors, amorphous clusters were produced in the cascade core whereas, in metals, most of the crystal regenerated; leaving only small vacancy-rich clusters. Large interstitial clusters which were sometimes found in heavy metals were observed to form via the isolation of a high-density liquid zone during the recrystallization phase of a cascade.

K.Nordlund, M.Ghaly, R.S.Averback, M.Caturla, T.Diaz de la Rubia, J.Tarus: Physical Review B, 1998, 57[13], 7556-70