Molecular dynamics simulation of defect formation in an aluminum crystal under low-energy ion bombardment

Atomic collision cascades initiated by Ar and Xe ions (with energies of 25, 40, and 50 eV) normally incident on the Al(100) crystal surface at a cryst al temperature of 300 K have been simulated by the molecular dynamics techn ique. The formation of vacancies and radiation-adsorbed and interstitial at oms in a cascade is discussed. It is demonstrated that the numbers of surfa ce and bulk vacancies formed in cascades under bombardment of the Al(100) s urface by Xe ions reach two maxima within 0.2-0.3 and 0.7-1.0 ps after the cascade initiation, whereas the number of vacancies generated under bombard ment by Ar ions reaches one maximum within 0.2-0.3 ps after the cascade ini tiation. (C) 2001 MAIK "Nauka/Interperiodica".